A hott or cute girl, usually a frosh in college or around that age. It's a positive nickname and can be used as term of endearment between friends or by couples. It can also be used by male creepers. (See below.)
Note: There is NO 'S' at the end of babycake! If a guy is calling you and your friend "babycakes" when you're all together, he's probably playing you.
Creeper usage: "Hey babycake, how you doin'??"
Couple usage: "I miss you, babycake!"
Friendly/Familial usage: "Awww, babycake it'll be ok!"