noun
flap
flap
noun
1
A flat piece attached along one edge that can hang loose or swing, such as on an envelope, pocket, or tent.
"She sealed the flap of the envelope."
2
A hinged panel on an aircraft wing used to control lift.
"The pilot lowered the flaps before landing."
3
(informal) A sudden fuss, panic, or scandal.
"There was a big flap in the office over the leaked memo."
verb
1
To move up and down or back and forth, especially a wing or something loose.
"The bird flapped its wings and took off."
"The tent flap flapped loudly in the wind."
How to Use Flap
Learner’s notesIn plain EnglishA loose hinged piece that swings or hangs (on an envelope, plane wing, pocket), or to move something that way; informally, also a sudden panic or fuss.
Common pairings
flap its wings
in a flap
pocket flap
Word Forms
flapped past tense, flaps plural, flaps singular
Study it as flashcards or scroll it in Flow — saved to your collection.
Test yourself on “flap”
A quick quiz — meaning, synonyms & usage
→
Fill the Gap
Can you complete this real example?
She sealed the _____ of the envelope.
Etymology
From Middle English flappe, "a slap or blow," related to the idea of something loose striking against something else.