The term "reflexive" refers to a situation where an action or response is directed back upon itself. In grammar, it describes verbs that indicate the subject performs an action on itself, such as in the sentence "She washed herself." This concept is important in understanding how certain languages structure sentences and convey meaning. In mathematics, "reflexive" often describes a relation where every element is related to itself. For example, in a set A, B, C, the relation is reflexive if A is related to A, B to B, and C to C. This property is essential in various fields, including set theory and logic.