Cover or covers might refer to:



Science and technology

Deception and concealment


  • Cover (topology), the mathematical concept of a collection of subsets of a set whose union is the whole set
  • Good cover (algebraic topology), an open topological cover such that all open sets in the cover and all intersections of finitely a large number of open sets are contractible
  • Cover (algebra), the concept of an algebraic structure that maps onto another structure in structure-preserving fashion
  • A pair in the covering relation of a partially ordered set, or the greater element in such a pair
  • A covering space, in the theory of Riemann surfaces and topology
  • A (universal / double), covering group, a covering space with group structure, common in theoretical physics
  • Cover, an equivalent set of constraints in database theory




  • Cover charge, an entry fee
  • Cover (law), a remedy for the breach of a contract for the receipt of goods
  • Cover (finance), repurchasing a short order made on the stock/equity, forex or futures markets
  • Smartphone cover
  • First day cover ("FDC" additionally called a first day of issue), a postage stamp on a cover, postal card or stamped envelope franked on the first day of issue

Other uses