noun (ejection seat, ejection seats)

1. A seat in an aircraft which can be ejected from the cockpit and thus save the pilots life when a crash is imminent.

noun <!-- Note: If you edit this, don't change position of Silo, it is referenced there as definition 2 in elevator
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1. Platform used for the moving of people and/or goods up and down in buildings.
2. A silo used for storing wheat, corn or other grain (grain elevator)
3. A control surface of an aircraft responsible for controling the pitching motion of the machine.
4. Trademark for a type of shoe having an insert lift to make the wearer appear taller.

noun

1. a moveable surface at the trailing edge of a tailless airplane (such as the space shuttle) that provides pitch and roll control

noun

1. The tail assembly of an aircraft.
2. The feathers of an arrow or the tail fins of a bomb or rocket used to stabilize the longitudinal axis of the projectile parallel to the flight path.

noun (plural envelopes)

1. A paper or cardboard wrapper used to enclose and small, flat items, especially letters, for mailing.
2. Something that envelops; a wrapping
3. A bag containing the lifting gas of a balloon or airship.
4. (geometry) A mathematical curve, surface, or higher-dimensional object that is the tangent to a given family of lines, curves, surfaces, or higher-dimensional objects.
5. (electronics) A curve that bounds another curve or set of curves, as the modulation envelope of an amplitude-modulated carrier wave in electronics.
6. (music) The shape of a sound, which may be controlled by a synthesizer or sampler.
7. (computing) The information used for routing an email that is transmitted with the email but not part of its contents.
8. (biology) An enclosing structure or cover, such as a membrane.
9. (engineering) The set of limitations within which a technological system can perform safely and effectively.