Contraction

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 ' (2015) which directed by Josh Forbes