1. an attribute of an object or event that plays an important role in distinguishing it from other objects or events and in the formation of category judgments. For example, a particular nose is a feature of one person’s face, wings are a feature of the category bird, particular lines and angles are features of a particular shape, line segments of various types are features of letters, and so on.

2. in phonemics, an attribute of a speech sound, such as whether it is voiced or unvoiced, that plays a critical role in distinguishing one phoneme from another. See binary feature; minimal pair.