In mathematics, specifically in category theory, hom-sets, i.e. sets of morphisms between objects, give rise to important functors to the category of sets. These functors are called hom-functors and have numerous applications in category theory and other branches of mathematics. == Formal definition == Let C be a locally small category (i.e. a category for which hom-classes are actually sets and not proper classes). For all objects A and B in C we define two functors to the category of sets as follows: The functor Hom(–,B) is also called the functor of points of the object B. Note that fixing the...

The claim that Eskimo languages have an unusually large number of words for snow is a widespread idea first voiced by Franz Boas and often used as a cliché when writing about how language may keep us more or less alert to the differences of the natural world. In fact, the Eskimo–Aleut languages have about the same number of distinct word roots referring to snow as English does, but the structure of these languages tends to allow more variety as to how those roots can be modified in forming a single word. A good deal of the ongoing debate thus depends on how one defines "word", and perhaps even...