|Origin:||enveloppe, from Old French envoloper; ENVELOP|
en‧ve‧lope S3 [countable]
a thin paper cover in which you put and send a letter: ➔ sae, SASE
envelopes and stamps
She tore open the envelope and frantically read the letter.
He got a job stuffing envelopes (=filling them with letters) at the campaign headquarters.
a layer of something that surrounds something else
an envelope of gases around the planet
3 American English
to try to go beyond the normal limits of something:
a musician who pushes the envelope of improvisation