Th is a digraph in the Latin script. It was originally introduced into Latin to transliterate Greek loan words. In modern languages that use the Latin alphabet, it represents a number of different sounds. It is the most common digraph in order of frequency in the English language.

Aspirated stop /tʰ/

The digraph was first introduced in Latin to transliterate the letter theta in loans from Greek. Theta was pronounced as an aspirated stop in Classical and early Koine Greek. is used in academic transcription systems to represent letters in south and east Asian alphabets that have the value . According to the Royal Thai General System of Transcription, for example, represents a series of Thai letters with the value . is also used to transcribe the phoneme in Southern Bantu languages, such as Zulu and Tswana.

Voiceless fricative /θ/

During late antiquity, the Greek phoneme represented by the letter mutated from an aspirated stop to a dental fricative . This mutation affected the pronunciation of , which began to be used to represent the phoneme in some of the languages that had it. One of the earliest languages to use the digraph this way was Old High German, before the final phase of the High German consonant shift, in which and came to be pronounced . In early Old English of the 7th and 8th centuries, the digraph was used until the Old English Latin alphabet adapted the runic letter ( thorn), as well as ( eth; in Old English), a modified version of the Latin letter , to represent this sound. Later, the digraph reappeared, gradually superseding these letters in Middle English. In modern English, an example of the digraph pronounced as is the one in ''tooth''. In Old and Middle Irish, was used for as well, but the sound eventually changed into (see below). Other languages that use for include Albanian and Welsh, both of which treat it as a distinct letter and alphabetize it between and .

Voiced fricative /ð/

English also uses to represent the voiced dental fricative , as in ''father''. This unusual extension of the digraph to represent a voiced sound is caused by the fact that, in Old English, the sounds and stood in allophonic relationship to each other and so did not need to be rigorously distinguished in spelling. The letters and were used indiscriminately for both sounds, and when these were replaced by in the 15th century, it was likewise used for both sounds. (For the same reason, is used in English for both and .) In the Norman dialect Jèrriais, the French phoneme is realized as , and is spelled under the influence of English.

Voiceless retroflex stop /ʈ/

In the Latin alphabet for the Javanese language, is used to transcribe the phoneme voiceless retroflex stop , which is written as in the native Javanese script.

Alveolar stop /t/

Because neither nor were native phonemes in Latin, the Greek sound represented by came to be pronounced . The spelling retained the digraph for etymological reasons. This practice was then borrowed into German, French, Dutch and other languages, where still appears in originally Greek words, but is pronounced . See German orthography. Interlingua also employs this pronunciation. In early modern times, French, German and English all expanded this by analogy to words for which there is no etymological reason, but for the most part the modern spelling systems have eliminated this. Examples of unetymological in English are the name of the River Thames from Middle English and the name '' Anthony'' (though the is often pronounced under the influence of the spelling) from Latin . In English, for can also occur in loan-words from French or German, such as ''Neanderthal''. The English name '' Thomas'' has initial because it was loaned from Norman.

Dental stop /t̪/

In the transcription of Australian Aboriginal languages represents a dental stop, .

/h/

In Irish and Scottish Gaelic, represents the lenition of . In most cases word-initially, it is pronounced . For example: Irish and Scottish Gaelic 'will' → 'your will'. This use of digraphs with to indicate lenition is distinct from the other uses which derive from Latin. While it is true that the presence of digraphs with in Latin inspired the Goidelic usage, their allocation to phonemes is based entirely on the internal logic of the Goidelic languages. Lenition in Gaelic lettering was traditionally denoted in handwriting using an overdot but typesetters lacked these pre-composed types and substituted a trailing . It is also a consequence of their history: the digraph initially, in Old and Middle Irish, designated the phoneme , but later sound changes complicated and obscured the grapheme–sound correspondence, so that is even found in some words like Scottish Gaelic 'sister' that never had a to begin with. This is an example of "inverted (historical) spelling": the model of words where the original interdental fricative had disappeared between vowels caused to be reinterpreted as a marker of hiatus.

Ø

The Irish and Scottish Gaelic lenited is silent in final position, as in Scottish Gaelic 'tired'. And, rarely, it is silent in initial position, as in Scottish Gaelic 'you'. In English, the in ''asthma'' and ''clothes'' is often silent.

ᵺ

is used for phonetic notation in some dictionaries.

Footnotes

{{DEFAULTSORT:Th (Digraph) English th Latin-script digraphs Graphemes