Girl crush refers to the admiration or adoration that one girl has for another girl. It could be to do with hair, body, make-up, car, clothes, career, talents etc.

Girl crush指一個女孩對另一個女孩的仰慕和喜愛之情，這種感情可能跟發型、身材、妝容、座駕、衣裝、事業以及才華等有關。

A key element to the girl crush is arguably the appearance of the crushee, and yet the classic girl crush is decidedly nonsexual. They may just want to be the crushee’s best friend. (Source: urbandictionary.com)

女孩之間這種喜愛之情的關鍵因素可能是被喜愛那一方的外表，不過，標準的女孩喜愛之情絕對跟性無關，她們可能只是想跟自己欣賞的女孩子做好朋友而已。