1 definition by futchkoleepoels
When a person doesn't know hot to kiss and either 1) sits there with a limp, half-open mouth and slobers all over your face or 2) puckers up and is otherwise unresponsive.
Kev: Yo man, that girl Cheyanne totally flatlined me, ugh.
Acquaintance: Ew dude, I hate flatlining! What did you do then?
Kev: I dumped her, HA!
Acquaintance: Ew dude, I hate flatlining! What did you do then?
Kev: I dumped her, HA!
by futchkoleepoels September 7, 2015