What does Ambuslap mean?

Ambuslap meaning in Urban Dictionary

A verb that defines the activity of silly people (mainly cops and firefighters) which always close the trunk doorways of a mutual help ambulance for EMTs after which slap the trunk doorways, generally twice in fast succession. That is expected to inform the out-of-town driver (at the front end for the ambulance) that they are now clear to go out of the scene, in the place of listening to the trained EMT who's in the rear of the ambulance and actually understands when it's ok to leave.