define

A kind of macro in source code that replaces one text string with another wherever it occurs.

To determine with precision; to mark out with distinctness; to ascertain or exhibit clearly.

“the defining power of an optical instrument”

To settle, decide (an argument etc.)

To express the essential nature of something.

“I define myself as a techno-anarchist.”

To state the meaning of a word, phrase, sign, or symbol.

“The textbook defined speed as velocity divided by time.”

To describe, explain, or make definite and clear; used to request the listener or other person to elaborate or explain more clearly his or her intended meaning of a word or expression.

“Person 1: Is she good at math?”

To demark sharply the outlines or limits of an area or concept.

“to define the legal boundaries of a property”

To establish the referent of a term or notation.