Contraction may refer to:
Linguistics
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Contraction (grammar)
A contraction is a shortened version of the spoken and written forms of a word, syllable, or word group, created by omission of internal letters and sounds.
In linguistic analysis, contractions should not be confused with crasis, abbreviation ...
, a shortened word
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Poetic contraction
Poetic contractions are contractions of words found in poetry but not commonly used in everyday modern English. Also known as elision or syncope, these contractions are usually used to lower the number of syllables in a particular word in order ...
, omission of letters for poetic reasons
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Elision
In linguistics, an elision or deletion is the omission of one or more sounds (such as a vowel, a consonant, or a whole syllable) in a word or phrase. However, these terms are also used to refer more narrowly to cases where two words are run to ...
, omission of sounds
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Syncope (phonology)
In phonology, syncope (; from ) is the loss of one or more sounds from the interior of a word, especially the loss of an unstressed vowel. It is found in both synchronic and diachronic analyses of languages. Its opposite, whereby sounds are adde ...
, omission of sounds in a word
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Synalepha
A synalepha or synaloepha is the merging of two syllables into one, especially when it causes two words to be pronounced as one.
The original meaning in Ancient Greek is more general than modern usage and includes coalescence of vowels within a ...
, merged syllables
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Synaeresis
In linguistics
Linguistics is the scientific study of language. The areas of linguistic analysis are syntax (rules governing the structure of sentences), semantics (meaning), Morphology (linguistics), morphology (structure of words), phone ...
, combined vowels
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Crasis
Crasis (; from the Greek , ); cf. , "I mix" ''wine with water''; '' kratēr'' "mixing-bowl" is related. is a type of contraction in which two vowels or diphthongs merge into one new vowel or diphthong, making one word out of two ( univerbation). ...
, merged vowels or diphthongs
Mathematics and logic
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Contraction (operator theory)
In operator theory, a bounded operator ''T'': ''X'' → ''Y'' between normed vector spaces ''X'' and ''Y'' is said to be a contraction if its operator norm , , ''T'' , , ≤ 1. This notion is a special case of the concept of a contra ...
, in operator theory, state of a bounded operator between normed vector spaces after suitable scaling
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Contraction hierarchies, in applied mathematics, a technique to speed up shortest-path routing
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Contraction mapping In mathematics, a contraction mapping, or contraction or contractor, on a metric space (''M'', ''d'') is a function ''f'' from ''M'' to itself, with the property that there is some real number 0 \leq k < 1 such that for all ''x'' and ...
, a type of function on a metric space
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Edge contraction
In graph theory, an edge contraction is an operation that removes an edge from a graph while simultaneously merging the two vertices that it previously joined. Edge contraction is a fundamental operation in the theory of graph minors. Vertex id ...
or vertex contraction, graph operations used in graph theory
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Tensor contraction
In multilinear algebra, a tensor contraction is an operation on a tensor that arises from the canonical pairing of a vector space and its dual. In components, it is expressed as a sum of products of scalar components of the tensor(s) caused by ...
, an operation on one or more tensors that arises from the natural pairing of a finite-dimensional vector space and its dual
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Left contraction and right contraction of multivectors in a geometric algebra, extensions of the inner product
* One of the rules of
conditional independence
In probability theory, conditional independence describes situations wherein an observation is irrelevant or redundant when evaluating the certainty of a hypothesis. Conditional independence is usually formulated in terms of conditional probabi ...
, in probability
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Contraction (logic)
In the logical discipline of proof theory, a structural rule is an inference rule of a sequent calculus that does not refer to any logical connective but instead operates on the sequents directly. Structural rules often mimic the intended meta-th ...
, a structural rule in proof theory
Medicine
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Muscle contraction
Muscle contraction is the activation of Tension (physics), tension-generating sites within muscle cells. In physiology, muscle contraction does not necessarily mean muscle shortening because muscle tension can be produced without changes in musc ...
, the physiological condition of a muscle which generates tension (traction) at its origin and insertion
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Uterine contraction
Uterine contractions are muscle contractions of the uterine smooth muscle that can occur at various intensities in both the non-pregnant and pregnant uterine state. The non-pregnant uterus undergoes small, spontaneous contractions in addition to ...
, contraction of the uterus, such as during childbirth
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Contractility
Contractility refers to the ability for self- contraction, especially of the muscles or similar active biological tissue
*Contractile ring in cytokinesis
*Contractile vacuole
*Muscle contraction
**Myocardial contractility
*See contractile cell fo ...
, the intrinsic ability of the heart/myocardium to contract
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Wound contraction
Wound contracture is a process that may occur during wound healing when an excess of Wound healing#Contraction, wound contraction, a normal healing process, leads to physical deformity characterized by skin constriction and functional limitations. ...
, a stage in wound healing
Other uses
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Contraction (economics)
In economics, a recession is a business cycle contraction that occurs when there is a period of broad decline in economic activity. Recessions generally occur when there is a widespread drop in spending (an adverse demand shock). This may be t ...
, a general slowdown in economic activity; the opposite of economic expansion
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Contraction (physics)
Thermal expansion is the tendency of matter to increase in length, area, or volume, changing its size and density, in response to an increase in temperature (usually excluding phase transitions).
Substances usually contract with decreasing temp ...
, change in the volume of matter in response to a change in temperature
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Lanthanide contraction
The lanthanide contraction is the greater-than-expected decrease in atomic radii and ionic radii of the elements in the lanthanide series, from left to right. It is caused by the poor shielding effect of nuclear charge by the 4f electrons alo ...
, the decrease in size of the ionic radius of lanthanide elements with their growing atomic number
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''Contracted'' (film), a 2013 horror thriller film by Eric England and its sequel ''
Contracted: Phase II'' (2015) which directed by Josh Forbes
See also
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Contract (disambiguation)
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Contraction principle (disambiguation)
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