(topology) Of a topological space: such that, for every point of the space, there is a neighborhood of that point whose closure is compact.

(mathematical analysis, of a set in a topological space) That is expressible as a countable union of compact sets.

plural of compact disc

plural of compact disk

A kind of optical disc used to store audio or other data.

A form of digital media on a plastic disc read by a laser in a CD drive. It comes in several varieties including CD-ROM, CD-R, and CD-RW.

(mathematics) Any topological subset of Euclidean space that is a compact set

plural of compact space

(US) Any of several agreements, comparable to treaties, between states of the United States

(topology, of a space) In which has every open cover has a finite subcover / (mathematics, of a morphism) Having open affine subschemes