- [noun] a flat rectangular paper container for papers
- [noun] any wrapper or covering
- [noun] a curve that is tangent to each of a family of curves
- [noun] a natural covering (as by a fluid); "the spacecraft detected an envelope of gas around the comet"
- [noun] the maximum operating capability of a system; "test pilots try to push the envelope"
- [noun] the bag containing the gas in a balloon
- Search for synonyms for ENVELOPE