envelope

/'enviloup/

Thân thiện

A woman places a letter into a white envelope.

Definition

1. Noun:
   • A flat, usually rectangular paper container for a letter or document: A folded and sealed paper cover used to hold and protect written correspondence for mailing or delivery.
   • A wrapper or covering that encloses something: Any outer layer or structure that surrounds and contains an object, substance, or space.
   • A natural or technical covering: A layer of material or a region of a substance that surrounds something else, such as a gas or fluid.
   • A mathematical concept: A curve or surface that is tangent to every member of a given family of curves or surfaces.
   • A set of performance limits: The established boundaries of capability for a system, especially an aircraft, often expressed as a combination of factors like speed, altitude, and load.

Usage Examples

• Noun:
  • She sealed the letter inside a white envelope.
  • The spacecraft entered the planet's gaseous envelope.
  • The engineer analyzed the aircraft's performance envelope.
  • In geometry, we calculated the envelope of the family of curves.

Advanced Usage

• "To push the envelope": To attempt to expand the known limits or boundaries of what is possible, often in technology, performance, or ideas.
  • The research team aims to push the envelope of battery technology.

Variants and Related Words

• Envelop (verb): To completely surround or cover something.
  • Fog began to envelop the entire valley.

Synonyms

• Wrapper: A covering or container.
• Sheath: A close-fitting cover.
• Casing: An outer shell or covering.
• Container: An object for holding something.

Related Phrases

• Performance envelope: The complete range of operating conditions for a machine or system.
  • The new engine design significantly widens the vehicle's performance envelope.

Related Idioms

• Push the envelope: To approach or go beyond the limits of what is normally done.
  • As an artist, he constantly tries to push the envelope.

Học thuật

Noun

1. the bag containing the gas in a balloon
2. the maximum operating capability of a system (especially an aircraft)
   • test pilots try to push the envelope
3. a natural covering (as by a fluid)
   • the spacecraft detected an envelope of gas around the comet
4. a curve that is tangent to each of a family of curves
5. any wrapper or covering
6. a flat (usually rectangular) container for a letter, thin package, etc.

Từ đồng nghĩa

• gasbag