Envelope (Noun)
Meaning 1
A natural covering (as by a fluid); "the spacecraft detected an envelope of gas around the comet".
Classification
Nouns denoting natural objects (not man-made).
Examples
- The spacecraft detected an envelope of gas around the comet as it approached the inner solar system.
- The team of scientists studied the envelope of warm air that surrounded the volcano, trying to understand its effects on the local climate.
- The oil spill was contained within a fragile envelope of booms and barriers, preventing it from spreading further.
- The embryo developed within a protective envelope of membranes that nourished and shielded it from the outside environment.
- The hurricane's outer rain bands formed an envelope of precipitation that stretched for hundreds of miles, bringing heavy rain and strong winds to the coastal regions.
Hypernyms
Meaning 2
The maximum operating capability of a system (especially an aircraft); "test pilots try to push the envelope".
Classification
Nouns denoting attributes of people and objects.
Hypernyms
Meaning 3
A curve that is tangent to each of a family of curves.
Classification
Nouns denoting two and three dimensional shapes.
Examples
- The envelope of the family of circles is a cardioid curve that touches each circle at a single point.
- In differential geometry, the envelope of a family of curves is a curve that is tangent to each member of the family.
- The problem of finding the envelope of a family of curves is a classic problem in calculus.
- The envelope of the family of parabolas is a parabolic curve that is tangent to each parabola in the family.
- The concept of an envelope is used in physics to describe the shape of a curve that is tangent to each of a family of curves, such as the shape of a shock wave.
Hypernyms
Meaning 4
A flat (usually rectangular) container for a letter, thin package, etc..
Classification
Nouns denoting man-made objects.
Meaning 6
The bag containing the gas in a balloon.
Classification
Nouns denoting man-made objects.
Examples
- The envelope of the hot air balloon was made of a lightweight yet strong material to withstand the heat and pressure.
- The envelope of the helium-filled balloon was a vibrant shade of red that caught everyone's attention.
- The elasticity of the envelope allowed the balloon to expand and contract as it rose and fell in the air.
- The envelope of the gas bag was carefully inflated with a mixture of hydrogen and helium to achieve the desired buoyancy.
- The envelope of the party balloon popped loudly when it was pinched too tightly by the excited child.