flap in WordNet English dictionary

1. move with a flapping motion
   "The bird's wings were flapping"
   beat  flap 
   
2. move with a thrashing motion
   "The bird flapped its wings"; "The eagle beat its wings and soared high into the sky"
   beat  flap 
   
3. make a fuss; be agitated
   dither  flap  pother 
   
4. pronounce with a flap, of alveolar sounds
   flap 
   
5. move noisily
   "flags flapped in the strong wind"
   flap 
   
6. move in a wavy pattern or with a rising and falling motion
   "The curtains undulated"; "the waves rolled towards the beach"
   roll  undulate  flap  wave 
   

1. an excited state of agitation
   "he was in a dither"; "there was a terrible flap about the theft"
   dither  pother  fuss  tizzy  flap 
   
2. any broad thin and limber covering attached at one edge; hangs loose or projects freely
   "he wrote on the flap of the envelope"
   flap 
   
3. a movable airfoil that is part of an aircraft wing; used to increase lift or drag
   flap  flaps 
   
4. a movable piece of tissue partly connected to the body
   flap 
   
5. the motion made by flapping up and down
   flap  flapping  flutter  fluttering