envelope

/ˈɛnvəloʊp/

/ˈenvɛləʊp/

Other forms: envelopes

An envelope is something that envelops, or wraps around. It usually refers to the thing you stick a stamp on and snail mail.

In the early 1700s, envelope, the noun for "wrapper," evolved from the French enveloppe, meaning “to envelop.” Envelope is always a noun, unlike the verb envelop which means “to wrap, cloak.” Synonyms for envelope range from casing and enclosure to pouch and sheath. Virginia Woolf said, “Life is a luminous halo, a semi-transparent envelope surrounding us from the beginning.” She ditched hers by walking into a river with her pockets full of rocks.

Definitions of envelope

1. noun

   a flat (usually rectangular) container for a letter, thin package, etc.
   types:

   window envelope

   an envelope with a transparent panel that reveals the address on the enclosure

   type of:

   container

   any object that can be used to hold things (especially a large metal boxlike object of standardized dimensions that can be loaded from one form of transport to another)
2. noun

   any wrapper or covering
   type of:

   wrap, wrapper, wrapping

   the covering (usually paper or cellophane) in which something is wrapped
3. noun

   a natural covering (as by a fluid)
   “the spacecraft detected an envelope of gas around the comet”

   type of:

   cover, covering, natural covering

   a natural object that covers or envelops
4. noun

   the bag containing the gas in a balloon
   synonyms: gasbag

   type of:

   bag

   a flexible container with a single opening
5. noun

   a curve that is tangent to each of a family of curves
   type of:

   curve, curved shape

   the trace of a point whose direction of motion changes
6. noun

   the maximum operating capability of a system (especially an aircraft)
   “test pilots try to push the envelope”

   type of:

   operating capability, performance capability

   the capability of a technological system to perform as intended