When the fat on a woman (or man) doesn't just go over the edge of the jeans (as in muffintop), but spills down them as well.
You see that muffintop over there? No, Jim, she is most definitely a boilover.
by IrishPh3n0m February 29, 2012
A not so spectacular ejaculation! A male orgasm that lacks significant distance.
A great porn scene building up to a huge ejaculation, and all it was, was a meaningless boil over!
by Captain Wacky August 23, 2007
Australian horseracing slang for the unexpected defeat of a hot favourite; a surprise result. Later used in contexts outside horseracing for an unexpected result in any context.
Bulgarian Tszvetana Pironkova, the world No.94, caused one of the biggest boilovers on Rod Laver Arena when she came from behind to record a 2-6 6-0 9-7 victory over Venus Williams.
by Quintius January 15, 2006
A dribbling orgasm instead of an explosion. Also experienced by old people.
After too many orgasms, the guy only had a boilover
by cartman197 September 14, 2006