Make out

[Sonia]

the act of swapping spit with your significant other... or perhaps just some hottie you met at a party, but anyway, you just sit there sucking at eachothers faces for an extended period of time and if youre lucky there might even be a little romming around of the hands if ya get my drift :p

[Becky]

a form of kissing characterized by its long duration of time, and often involves what can be described as french kissing.

term used most often by teenagers.

[PussyCat]

tongue-ing and a lot of touching

[Tina]

when two people kiss excessively: usually for 2 minutes or more; french kissing for long periods of time

[Luis Fok]

to engage in prolonged kissing and possibly petting

[Couch Potatoe]

Kissing... a lot. It could be defined as foreplay in some cases, though.