presheaf

Meaning

Noun

• A contravariant functor whose domain is a category whose objects are open sets of a topological space and whose morphisms are inclusion mappings. The functorial images of the open sets are sets of things called sections which are said to be "over" those open sets. The (contravariant) functorial images of those inclusion mappings are functions which are called restrictions.

Related

Narrower meaning words

• sheaf

Origin

• pre- + sheaf