Urban dictionary: Babykiller:

1/ A drink consisting of straight vodka on the rocks. Babykillers are rated on a scale of 1-10, based on the amount of babies they could kill. Generally, cheaper vodkas will increase the bk content.

2/ A derogatory term used to identify Vietnam-era veterans returning from the war in the late 1960's and early 1970's.

3/ One that takes the time to kill a baby.

4/ A term used to describe a girl's shoes when used to kick a guys nuts.