A mora (plural ''morae'' or ''moras''; often symbolized μ) is a smallest unit of
timing
Timing is the tracking or planning of the spacing of events in time. It may refer to:
* Timekeeping, the process of measuring the passage of time
* Synchronization, controlling the timing of a process relative to another process
* Time metrolo ...
, equal to or shorter than a
syllable
A syllable is a basic unit of organization within a sequence of speech sounds, such as within a word, typically defined by linguists as a ''nucleus'' (most often a vowel) with optional sounds before or after that nucleus (''margins'', which are ...
, that theoretically or perceptually exists in some spoken languages in which
phonetic length (such as
vowel length
In linguistics, vowel length is the perceived or actual length (phonetics), duration of a vowel sound when pronounced. Vowels perceived as shorter are often called short vowels and those perceived as longer called long vowels.
On one hand, many ...
) matters significantly. For example, in the
Japanese language
is the principal language of the Japonic languages, Japonic language family spoken by the Japanese people. It has around 123 million speakers, primarily in Japan, the only country where it is the national language, and within the Japanese dia ...
, the name of the city ''
Ōsaka'' () consists of three syllables (''O-sa-ka'') but four morae (), since the first syllable, ''Ō'', is pronounced with a
long vowel
In linguistics, vowel length is the perceived or actual duration of a vowel sound when pronounced. Vowels perceived as shorter are often called short vowels and those perceived as longer called long vowels.
On one hand, many languages do not d ...
(the others being short). Thus, a short vowel contains one mora and is called ''monomoraic'', while a long vowel contains two and is called ''bimoraic''. Extra-long syllables with three morae (''trimoraic'') are relatively rare. Such metrics based on syllables are also referred to as
syllable weight
In linguistics, syllable weight is the concept that syllables pattern together according to the number and/or duration of segments in the rime. In classical Indo-European verse, as developed in Greek, Sanskrit, and Latin, distinctions of syllabl ...
. In Japanese, certain consonants also stand on their own as individual morae and thus are monomoraic.
The term comes from the
Latin
Latin ( or ) is a classical language belonging to the Italic languages, Italic branch of the Indo-European languages. Latin was originally spoken by the Latins (Italic tribe), Latins in Latium (now known as Lazio), the lower Tiber area aroun ...
word for 'linger, delay', which was also used to translate the Greek word : ('time') in its
metrical sense.
Formation
The general principles for assigning moras to segments are as follows (see
Hayes 1989 and
Hyman 1985 for detailed discussion):
# A
syllable onset
A syllable is a basic unit of organization within a sequence of speech sounds, such as within a word, typically defined by linguists as a ''nucleus'' (most often a vowel) with optional sounds before or after that nucleus (''margins'', which are ...
(the first
consonant
In articulatory phonetics, a consonant is a speech sound that is articulated with complete or partial closure of the vocal tract, except for the h sound, which is pronounced without any stricture in the vocal tract. Examples are and pronou ...
or consonants of the syllable) does not represent any mora.
# The
syllable nucleus
A syllable is a basic unit of organization within a sequence of speech sounds, such as within a word, typically defined by linguists as a ''nucleus'' (most often a vowel) with optional sounds before or after that nucleus (''margins'', which are ...
represents one mora in the case of a short vowel, and two morae in the case of a long vowel or
diphthong
A diphthong ( ), also known as a gliding vowel or a vowel glide, is a combination of two adjacent vowel sounds within the same syllable. Technically, a diphthong is a vowel with two different targets: that is, the tongue (and/or other parts of ...
. Consonants serving as syllable nuclei also represent one mora if short and two if long.
Slovak is an example of a language that has both long and short consonantal nuclei.
# In some languages (for example,
Latin
Latin ( or ) is a classical language belonging to the Italic languages, Italic branch of the Indo-European languages. Latin was originally spoken by the Latins (Italic tribe), Latins in Latium (now known as Lazio), the lower Tiber area aroun ...
and
Japanese), the
coda represents one mora, and in others (for example,
Irish) it does not.
# In some languages, a syllable with a long vowel or diphthong in the nucleus and one or more consonants in the coda is said to be trimoraic (syllables exhibiting
pluti
Vedic Sanskrit, also simply referred as the Vedic language, is the most ancient known precursor to Sanskrit, a language in the Indo-Aryan languages, Indo-Aryan subgroup of the Indo-European languages, Indo-European language family. It is atteste ...
in Sanskrit).
In general, monomoraic syllables are called "light syllables", bimoraic syllables are called "heavy syllables", and trimoraic syllables (in languages that have them) are called "superheavy syllables". Some languages, such as
Old English
Old English ( or , or ), or Anglo-Saxon, is the earliest recorded form of the English language, spoken in England and southern and eastern Scotland in the Early Middle Ages. It developed from the languages brought to Great Britain by Anglo-S ...
and potentially present-day English, can have syllables with up to four morae.
A
prosodic
In linguistics, prosody () is the study of elements of speech, including intonation (linguistics), intonation, stress (linguistics), stress, Rhythm (linguistics), rhythm and loudness, that occur simultaneously with individual phonetic segments: v ...
stress system in which moraically heavy syllables are assigned stress is said to have the property of quantity sensitivity.
Languages
Ancient Greek
For the purpose of determining accent in
Ancient Greek
Ancient Greek (, ; ) includes the forms of the Greek language used in ancient Greece and the classical antiquity, ancient world from around 1500 BC to 300 BC. It is often roughly divided into the following periods: Mycenaean Greek (), Greek ...
, short vowels have one mora, and long vowels and diphthongs have two morae. Thus long ''ē'' (
eta
Eta ( ; uppercase , lowercase ; ''ē̂ta'' or ''ita'' ) is the seventh letter of the Greek alphabet, representing the close front unrounded vowel, . Originally denoting the voiceless glottal fricative, , in most dialects of Ancient Greek, it ...
: ) can be understood as a sequence of two short vowels: ''ee''.
Ancient Greek pitch accent is placed on only one mora in a word. An
acute (, ) represents high pitch on the only mora of a short vowel or the last mora of a long vowel (''é'', ''eé''). A
circumflex
The circumflex () is a diacritic in the Latin and Greek scripts that is also used in the written forms of many languages and in various romanization and transcription schemes. It received its English name from "bent around"a translation of ...
() represents high pitch on the first mora of a long vowel (''ée'').
Gilbertese
Gilbertese, an
Austronesian language
The Austronesian languages ( ) are a language family widely spoken throughout Maritime Southeast Asia, parts of Mainland Southeast Asia, Madagascar, the islands of the Pacific Ocean and Taiwan (by Taiwanese indigenous peoples). They are spoken b ...
spoken mainly in
Kiribati
Kiribati, officially the Republic of Kiribati, is an island country in the Micronesia subregion of Oceania in the central Pacific Ocean. Its permanent population is over 119,000 as of the 2020 census, and more than half live on Tarawa. The st ...
, is a trimoraic language. The typical
foot
The foot (: feet) is an anatomical structure found in many vertebrates. It is the terminal portion of a limb which bears weight and allows locomotion. In many animals with feet, the foot is an organ at the terminal part of the leg made up o ...
in Gilbertese contains three morae. These trimoraic constituents are units of stress in Gilbertese. These "ternary metrical constituents of the sort found in Gilbertese are quite rare cross-linguistically, and as far as we know, Gilbertese is the only language in the world reported to have a ternary constraint on prosodic word size."
Hawaiian
In
Hawaiian, both syllables and morae are important. Stress falls on the penultimate mora, though in words long enough to have two stresses, only the final stress is predictable. However, although a
diphthong
A diphthong ( ), also known as a gliding vowel or a vowel glide, is a combination of two adjacent vowel sounds within the same syllable. Technically, a diphthong is a vowel with two different targets: that is, the tongue (and/or other parts of ...
, such as ''oi,'' consists of two morae, stress may fall only on the first, a restriction not found with other vowel sequences such as ''io.'' That is, there is a distinction between ''oi,'' a bimoraic syllable, and ''io,'' which is two syllables.
Japanese
Most dialects of
Japanese, including the standard, use morae, known in Japanese as () or (), rather than syllables, as the basis of the sound system. Writing Japanese in
kana
are syllabary, syllabaries used to write Japanese phonology, Japanese phonological units, Mora (linguistics), morae. In current usage, ''kana'' most commonly refers to ''hiragana'' and ''katakana''. It can also refer to their ancestor , wh ...
(
hiragana
is a Japanese language, Japanese syllabary, part of the Japanese writing system, along with ''katakana'' as well as ''kanji''.
It is a phonetic lettering system. The word ''hiragana'' means "common" or "plain" kana (originally also "easy", ...
and
katakana
is a Japanese syllabary, one component of the Japanese writing system along with hiragana, kanji and in some cases the Latin script (known as rōmaji).
The word ''katakana'' means "fragmentary kana", as the katakana characters are derived fr ...
) demonstrates a moraic system of writing. For example, in the two-syllable word ', the ''ō'' is a long
vowel
A vowel is a speech sound pronounced without any stricture in the vocal tract, forming the nucleus of a syllable. Vowels are one of the two principal classes of speech sounds, the other being the consonant. Vowels vary in quality, in loudness a ...
and counts as two morae. The word is written in three symbols, , corresponding here to , each containing one mora. Therefore, the 5/7/5 pattern of the ''
haiku
is a type of short form poetry that originated in Japan. Traditional Japanese haiku consist of three phrases composed of 17 Mora (linguistics), morae (called ''On (Japanese prosody), on'' in Japanese) in a 5, 7, 5 pattern; that include a ''kire ...
'' in modern Japanese is of morae rather than syllables.
The Japanese syllable-final ''n'' is also moraic, as is the first part of a
geminate consonant
In phonetics and phonology, gemination (; from Latin 'doubling', itself from '' gemini'' 'twins'), or consonant lengthening, is an articulation of a consonant for a longer period of time than that of a singleton consonant. It is distinct from ...
. For example, the Japanese name for ''
Japan
Japan is an island country in East Asia. Located in the Pacific Ocean off the northeast coast of the Asia, Asian mainland, it is bordered on the west by the Sea of Japan and extends from the Sea of Okhotsk in the north to the East China Sea ...
'', , has two different pronunciations, one with three morae () and one with four (). In the hiragana spelling, the three morae of are represented by three characters (), and the four morae of need four characters to be written out as . The latter can also be analysed as , with the Q representing a full mora of silence. In this analysis, っ (the ''
sokuon
The is a Japanese typographic symbols, Japanese symbol in the form of a small hiragana or katakana , as well as the various consonants represented by it. In less formal language, it is called or , meaning "small ". It serves multiple purposes ...
'') indicates a one-mora period of silence.
Similarly, the names ''
Tōkyō
Tokyo, officially the Tokyo Metropolis, is the capital and most populous city in Japan. With a population of over 14 million in the city proper in 2023, it is one of the most populous urban areas in the world. The Greater Tokyo Area, which ...
'' (, ), ''
Ōsaka'' (, ), and ''
Nagasaki
, officially , is the capital and the largest Cities of Japan, city of Nagasaki Prefecture on the island of Kyushu in Japan.
Founded by the Portuguese, the port of Portuguese_Nagasaki, Nagasaki became the sole Nanban trade, port used for tr ...
'' (, ) all have four morae, even though, on this analysis, they have two, three and four syllables, respectively. The number of morae in a word is not always equal to the number of
grapheme
In linguistics, a grapheme is the smallest functional unit of a writing system.
The word ''grapheme'' is derived from Ancient Greek ('write'), and the suffix ''-eme'' by analogy with ''phoneme'' and other emic units. The study of graphemes ...
s when written in kana; for example, even though it has four morae, the Japanese name for () is written with five graphemes, because one of these graphemes () represents a ''
yōon
The is a feature of the Japanese language in which a mora is formed with an added sound, i.e., palatalized, or (more rarely in the modern language) with an added sound, i.e. labialized.
''Yōon'' are represented in hiragana using a kana end ...
'', a feature of the Japanese writing system that indicates that the preceding consonant is
palatalized.
The "contracted sound" () is represented by the three small kana for (), (), (). These do not represent a mora by themselves and attach to other kana; all the rest of the graphemes represent a on their own.
Most dialects of Japanese are
pitch accent
A pitch-accent language is a type of language that, when spoken, has certain syllables in words or morphemes that are prominent, as indicated by a distinct contrasting pitch (music), pitch (tone (linguistics), linguistic tone) rather than by vol ...
languages, and these
pitch accents are also based on morae.
There is a unique set of known as "special mora" () which cannot be pronounced by itself but still counts as one mora whenever present. These consist of "nasal sound" () represented by the kana for ''n'' (), the "geminate consonant" () represented by the small tsu (), the "long sound" () represented by the long vowel symbol () or a single vowel which extends the sound of the previous () and the "diphthong" () represented by the second vowel of two consecutive vowels ().
This set also has the peculiarity that – barring only a couple of extreme examples, namely コーン茶 and チェーン店 – the drop in pitch of a word (so-called "downstep") cannot come after any of these "special morae", a useful tidbit for language learners trying to learn word pitch accents.
Luganda
In
Luganda
Ganda or Luganda ( ; ) is a Bantu language spoken in the African Great Lakes region. It is one of the major languages in Uganda and is spoken by more than 5.56 million Ganda people, Baganda and other people principally in central Uganda, includ ...
, a
short vowel
In linguistics, vowel length is the perceived or actual duration of a vowel sound when pronounced. Vowels perceived as shorter are often called short vowels and those perceived as longer called long vowels.
On one hand, many languages do not ...
constitutes one mora while a
long vowel
In linguistics, vowel length is the perceived or actual duration of a vowel sound when pronounced. Vowels perceived as shorter are often called short vowels and those perceived as longer called long vowels.
On one hand, many languages do not d ...
constitutes two morae. A simple
consonant
In articulatory phonetics, a consonant is a speech sound that is articulated with complete or partial closure of the vocal tract, except for the h sound, which is pronounced without any stricture in the vocal tract. Examples are and pronou ...
has no morae, and a
doubled or
prenasalised consonant has one. No
syllable
A syllable is a basic unit of organization within a sequence of speech sounds, such as within a word, typically defined by linguists as a ''nucleus'' (most often a vowel) with optional sounds before or after that nucleus (''margins'', which are ...
may contain more than three morae. The tone system in Luganda is based on morae. See
Luganda tones and
Luganda grammar
Ganda or Luganda ( ; ) is a Bantu language spoken in the African Great Lakes region. It is one of the major languages in Uganda and is spoken by more than 5.56 million Ganda people, Baganda and other people principally in central Uganda, includ ...
.
Old English
In Old English, short diphthongs and monophthongs were monomoraic, long diphthongs and monophthongs were bimoraic, consonants ending a syllable were each one mora, and
geminate
In phonetics and phonology, gemination (; from Latin 'doubling', itself from '' gemini'' 'twins'), or consonant lengthening, is an articulation of a consonant for a longer period of time than that of a singleton consonant. It is distinct from ...
consonants added a mora to the preceding syllable. If Modern English is analyzed in terms of morae at all, which is contentious, the rules would be similar, except that all diphthongs would be considered bimoraic. Probably in Old English, like in Modern English, syllables could not have more than four morae, with loss of sounds occurring if a syllable would have more than four otherwise. In the Old English period, all
content word Content words, in linguistics, are words that possess semantic content and contribute to the meaning of the sentence in which they occur. In a traditional approach, nouns were said to name objects and other entities, lexical verbs to indicate acti ...
s (as well as stressed monosyllables) had to be at least two morae long.
Sanskrit
In
Sanskrit
Sanskrit (; stem form ; nominal singular , ,) is a classical language belonging to the Indo-Aryan languages, Indo-Aryan branch of the Indo-European languages. It arose in northwest South Asia after its predecessor languages had Trans-cultural ...
, the mora is expressed as the .
For example, the short vowel ''a'' (pronounced like a
schwa) is assigned a value of one , the long vowel is assigned a value of two s, and the compound vowel (diphthong) ''ai'' (which has either two simple short vowels, ''a''+''i'', or one long and one short vowel, ''ā''+''i'') is assigned a value of two s. In addition, there is (trimoraic) and ('long ' = quadrimoraic).
Sanskrit prosody and metrics have a deep history of taking into account moraic weight, as it were, rather than straight syllables, divided into (, 'light') and / (/, 'heavy') feet based on how many morae can be isolated in each word. Thus, for example, the word (), meaning 'agent' or 'doer', does not contain simply two syllabic units, but contains rather, in order, a /
foot
The foot (: feet) is an anatomical structure found in many vertebrates. It is the terminal portion of a limb which bears weight and allows locomotion. In many animals with feet, the foot is an organ at the terminal part of the leg made up o ...
and a foot. The reason is that the conjoined
consonants
In articulatory phonetics, a consonant is a speech sound that is articulated with complete or partial closure of the vocal tract, except for the h sound, which is pronounced without any stricture in the vocal tract. Examples are and pronou ...
''rt'' render the normally light ''ka''
syllable
A syllable is a basic unit of organization within a sequence of speech sounds, such as within a word, typically defined by linguists as a ''nucleus'' (most often a vowel) with optional sounds before or after that nucleus (''margins'', which are ...
heavy.
See also
*
Chroneme
In linguistics, a chroneme is an abstract phonological suprasegmental feature used to signify contrastive differences in the length of speech sounds. Both consonants and vowels can be viewed as displaying this features. The noun ''chroneme'' is ...
*
Compensatory lengthening
Compensatory lengthening in phonology and historical linguistics is the lengthening of a vowel sound that happens upon the loss of a following consonant, usually in the syllable coda, or of a vowel in an adjacent syllable. Lengthening triggered ...
*
Dreimorengesetz
*
On (Japanese prosody)
*
Pitch accent
A pitch-accent language is a type of language that, when spoken, has certain syllables in words or morphemes that are prominent, as indicated by a distinct contrasting pitch (music), pitch (tone (linguistics), linguistic tone) rather than by vol ...
*
Syllable
A syllable is a basic unit of organization within a sequence of speech sounds, such as within a word, typically defined by linguists as a ''nucleus'' (most often a vowel) with optional sounds before or after that nucleus (''margins'', which are ...
Notes
References
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LCCN
External links
*
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