As a verb plapper
is to make a noise with the lips.
As a noun plipper is
a remote-control device used to unlock a car without having to put the keys into the lock.
plapper
English
Verb
(
en verb)
to make a noise with the lips
:* 1922': She took no notice while he read by rote a solfa fable for her, '''plappering flatly — James Joyce, ''Ulysses plipper
English
Noun
(
en noun)
A remote-control device used to unlock a car without having to put the keys into the lock.