The admiraton one girl has for another. It could be to do with hair, body, make-up, car, clothes, career, talents etc. Completely non-sexual. Girl crushes are generally very short-lived, as girls move on very quickly from trends.

feelings of admiration and adoration which a girl has for another girl, without wanting to shag said girl. a nonsexual attraction, usually based on veneration at some level.

related to boy crush

an overwhelming sense of awe felt by a girl for another girl elicited by varying causes ranging from deep respect to unadulterated lust. may result in the any or all of the following: general euphoria, prolonged sense of inspiration, desire for intellectual-intercouse with crush, simple sexual arousal, etc

When a girl has a crush on another girl,
but they don't wanna date them.
It's more like they wanna be their best friend.

A female who absolutely adores another female in the most nonlesbian way and tries to be EXACTLY like that chick and forgets her identity.