Either sex can be a lush. It's someone who drinks a lot and enjoys drinking a lot---not necessarily an alcoholic, but someone whose drinking is noticeable. It can be used teasingly or as an insult, but even if someone teases you (or whoever), there's probably some truth in it, and it probably means you're overdoing the alcohol.
Sara is such a lush! Did you see her dancing at Firehaus? Oh em gee. It wasn't even her birthday!