definition of
contraction

[1] #1 contraction n. [muscular contraction, muscle contraction] (physiology) a shortening or tensing of a part or organ (especially of a muscle or muscle fiber). wn

[2] #2 contraction n. [compression, condensation] the process or result of becoming smaller or pressed together; "the contraction of a gas on cooling". wn

[3] #3 contraction n. a word formed from two or more words by omitting or combining some sounds; "'won't' is a contraction of 'will not'"; "'o'clock' is a contraction of 'of the clock'". wn

[4] #4 contraction n. the act of decreasing (something) in size or volume or quantity or scope. wn