Contraction

{{wiktionary|contraction|contracted}} '''Contraction''' may refer to: {{TOC right}}

== Linguistics == * Contraction (grammar), a shortened word * Poetic contraction, omission of letters for poetic reasons * Elision, omission of sounds ** Syncope (phonology), omission of sounds in a word * Synalepha, merged syllables ** Synaeresis, combined vowels ** Crasis, merged vowels or diphthongs

== Mathematics and logic == * Contraction (operator theory), in operator theory, state of a bounded operator between normed vector spaces after suitable scaling * Contraction hierarchies, in applied mathematics, a technique to speed up shortest-path routing * Contraction mapping, a type of function on a metric space * Edge contraction or vertex contraction, graph operations used in graph theory * Tensor contraction, an operation on one or more tensors that arises from the natural pairing of a finite-dimensional vector space and its dual * Interior product, a tensor contraction specifically of a differential form with a vector field * 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 * Contraction (logic), a structural rule in proof theory

== Medicine == *Muscle contraction, the physiological condition of a muscle which generates tension (traction) at its origin and insertion ** Uterine contraction, contraction of the uterus, such as during childbirth *Contractility, the intrinsic ability of the heart/myocardium to contract * Wound contraction, a stage in wound healing

== Other uses == * Contraction (economics), a general slowdown in economic activity; the opposite of economic expansion * Contraction (physics), change in the volume of matter in response to a change in temperature * Lanthanide contraction, the decrease in size of the ionic radius of lanthanide elements with their growing atomic number * ''Contracted'' (film), a 2013 horror thriller film by Eric England and its sequel ''Contracted: Phase II'' (2015) which directed by Josh Forbes