expansion vs contraction

expansion and contraction both are nouns.

Word	Noun	Adjective	Verb	Adverb
expansion	Yes	No	No	No
contraction	Yes	No	No	No

expansion (noun)	contraction (noun)
the act of increasing (something) in size or volume or quantity or scope	the act of decreasing (something) in size or volume or quantity or scope
adding information or detail	(physiology) a shortening or tensing of a part or organ (especially of a muscle or muscle fiber)
a discussion that provides additional information	a word formed from two or more words by omitting or combining some sounds
a function expressed as a sum or product of terms	the process or result of becoming smaller or pressed together