envelope

n. paper wrapper in which letters are sealed and sent

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Noun
1. a flat rectangular paper container for papers
(hypernym) container
(hyponym) window envelope
2. any wrapper or covering
(hypernym) wrapping, wrap, wrapper
3. a curve that is tangent to each of a family of curves
(hypernym) curve, curved shape
4. a natural covering (as by a fluid); "the spacecraft detected an envelope of gas around the comet"
(hypernym) covering, natural covering, cover
5. the maximum operating capability of a system; "test pilots try to push the envelope"
(hypernym) operating capability, performance capability
6. the bag containing the gas in a balloon
(synonym) gasbag
(hypernym) bag
(part-holonym) balloon

n. cover, envelope

n. obálka