envelope
PACKAGING ITEM, USUALLY MADE OF THIN FLAT MATERIAL
Envelopes; Envelope manufacture; ✉; Envelope size; ISO 269; Envelope sizes; No. 10 Envelope; No 10 Envelope; ISO 269:1985; 🖂; Monarch envelope
n.
1) to address; seal an envelope
2) a pay envelope (AE; BE has pay packet)
3) a self-addressed; stamped; window envelope
USAGE NOTE: AE has stamped self-addressed envelope; BE has stamped addressed envelope.