∙ A rank in a taxonomic classification, below species and subspecies. taxonomy
∙ The total number of distinct states of a system. cybernetics
∙ Logarithm of the base 2 of the total number of distinct states of a system. cybernetics
∙ A term used for a specific form of a language, neutral to whether that form is a dialect, accent, register, etc. and to its prestige level. linguistics
∙ The class of all algebraic structures of a given signature satisfying a given set of identities. algebra, esp. universal algebra
∙ The kind of theatrical entertainment given in variety shows.
∙ The production of, or performance in, variety shows.