envelope
A2Meanings
-
1
noun
the maximum operating capability of a system (especially an aircraft)
test pilots try to push the envelope
-
2
noun
a natural covering made out of liquid or gas
The spacecraft detected an envelope of gas around the comet.
-
3
noun
A paper or cardboard wrapper used to enclose small, flat items, especially letters, for mailing.
Now we are liberal with our innermost secrets, spraying them into the public ether with a generosity our forebears could not have imagined. Where we once sent love letters in a sealed envelope, or stuck photographs of our children in a family album, now such private material is despatched to servers and clouds operated by people we don't know and will never meet.
-
4
noun
A bag containing the lifting gas of a balloon or airship; fabric that encloses the gas-bags of an airship.
They have no internal or external support structure, being simply a fabric bag (or envelope) filled with a lighter than air gas. Inside the envelope are one or more "ballonets", or smaller bags, which help maintain the envelope's shape.
-
5
noun
The set of limitations within which a technological system can perform safely and effectively.
push the envelope
-
6
noun
An earthwork in the form of a single parapet or a small rampart, sometimes raised in the ditch and sometimes beyond it.
make a blind all along the bottom of the ditch of the Envelope
-
7
verb
To put (something) in an envelope.
Arthur Armytage drew the precious document from his bureau; and without trusting himself to a re-perusal, enveloped and re-enveloped—sealed and resealed it;—mounted his horse, and rode off to Greta Castle.
-
8
verb
Archaic form of envelop.
Again, if the plane of the impressed couple intersects the mean plane between N and C, it will envelope the cone whose focals are ON, ON′, and whose internal axis is therefore OA.
Etymology
PIE word *h₁én From French enveloppe. The engineering sense is derived from flight envelope. The verb is from the noun.
View etymology graph →