look up any word, like the eiffel tower:
A girl who a guy only sees on the weekends because he is not really serious about her. Typically, he is only with her because she is offering something to him on said weekends (ie, sex).
Q: I didn't know Carrie was John's girlfriend. A: Oh, she's only his weekend girlfriend, nothing serious, just sex mostly.
by Arealgirl August 31, 2012