|Origin:||Perhaps from the sound|
flap2 past tense and past participle flapped, present participle flapping
1 [intransitive and transitive]HBB
if a bird flaps its wings, it moves them up and down in order to fly
2 [intransitive and transitive]
to move quickly up and down or from side to side, often making a noise:
The flags were flapping in the breeze.
Flap your arms to keep warm.
3 [intransitive] British English informal
to behave in an excited or nervous way:
There's no need to flap!