noun, feminine/ɑ̃.vlɔp/plural: enveloppes
envelope (wrapper for mailing); envelope (of a family of curves); envelope (an enclosing structure or cover, such as a membrane)
Inherited from Middle French enveloppe, anveloppe, from Old French envelope (“that which envelops, a type of garment”), from envoloper, anveloper (“to wrap around, enfold, cover”).