definition of
flap

[1] #1 flap v. [roll, undulate, wave] move in a wavy pattern or with a rising and falling motion; "The curtains undulated"; "the waves rolled towards the beach". wn

[2] #2 flap n. any broad thin and limber covering attached at one edge; hangs loose or projects freely; "he wrote on the flap of the envelope". wn

[3] #3 flap v. move noisily; "flags flapped in the strong wind". wn

[4] #4 flap v. [beat] move with a thrashing motion; "The bird flapped its wings"; "The eagle beat its wings and soared high into the sky". wn

[5] #5 flap n. [dither, pother, fuss, tizzy] an excited state of agitation; "he was in a dither"; "there was a terrible flap about the theft". wn