Contraction may refer to:

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

See also

  • Contract (disambiguation)
  • Contraction principle (disambiguation)