defining a word by listing the class of entities to which the word correctly applies
例句
用作形容词 (adj.)
The familiar semantics for first-order logic is extensional in that it is involved in individual objects rather than in any property entities. 摘要熟知的一阶逻辑语义因为只论及个体对象而不涉及属性实体而被认为是外延的。