contraction

(noun) (physiology) a shortening or tensing of a part or organ (especially of a muscle or muscle fiber). Synonyms: muscular contraction, muscle contraction.

(noun) the process or result of becoming smaller or pressed together. Synonyms: compression, condensation. Example: "The contraction of a gas on cooling."

(noun) a word formed from two or more words by omitting or combining some sounds. Examples: "`won't' is a contraction of `will not'." "`o'clock' is a contraction of `of the clock'."

(noun) the act of decreasing (something) in size or volume or quantity or scope.