Macbook Dictionary defines define (sorry, I had to write that ):
state or describe exactly the nature, scope, or meaning of : the contract will seek to define the client’s obligations.
• give the meaning of (a word or phrase), esp. in a dictionary.
• make up or establish the character of : for some, the football team defines their identity.
2 mark out the boundary or limits of : [as adj. ] ( defined) clearly defined boundaries.
• make clear the outline of; delineate : she defined her eyes by applying eyeshadow.
ORIGIN late Middle English (also in the sense [bring to an end] ): from Old French definer, from a variant of Latin definire, from de- (expressing completion) + finire ‘finish’ (from finis ‘end’ ).