compact Adjective Closely packed, i.e. packing much in a small space.

compact Adjective Having all necessary features fitting neatly into a small space.

compact Adjective (of a set in an Euclidean space) Closed and bounded.

compact Adjective Such that every exhaustion of it by (overlapping) open balls has the property that some finitely many of those balls will also cover it.

compact Adjective ("of a set") Such that every open cover of the given set has a finite subcover.

compact Noun A small folding mirror containing powder that fits into a woman's purse or handbag.