An envelope is a common packaging item, usually made of thin, flat material. It is designed to contain a flat object, such as a letter or card. Traditional...

A red envelope, red packet, hongbao or ang pau (traditional Chinese: 紅包; simplified Chinese: 红包; pinyin: hóngbāo; Pe̍h-ōe-jī: âng-pau) is a gift of money...

In sound and music, an envelope describes how a sound changes over time. For example, a piano key, when struck and held, creates a near-immediate initial...

The nuclear envelope, also known as the nuclear membrane, is made up of two lipid bilayer membranes that in eukaryotic cells surround the nucleus, which...

In physics and engineering, the envelope of an oscillating signal is a smooth curve outlining its extremes. The envelope thus generalizes the concept of...

The envelope system, also known as the envelope budgeting method or cash stuffing, is a popular personal budgeting method for visualizing and maintaining...

An envelope detector (sometimes called a peak detector) is an electronic circuit that takes a (relatively) high-frequency signal as input and outputs the...

A stamped envelope or postal stationery envelope (PSE) is an envelope with a printed or embossed indicium indicating the prepayment of postage. It is...

Look up envelope in Wiktionary, the free dictionary. An envelope is the paper container used to hold a letter being sent by post. Envelope may also refer...

The two envelopes problem, also known as the exchange paradox, is a paradox in probability theory. It is of special interest in decision theory and for...

In aerodynamics, the flight envelope, service envelope, or performance envelope of an aircraft or spacecraft refers to the capabilities of a design in...

between host cells. Not all viruses have envelopes. A viral envelope protein or E protein is a protein in the envelope, which may be acquired by the capsid...

In geometry, an envelope of a planar family of curves is a curve that is tangent to each member of the family at some point, and these points of tangency...

self-addressed stamped envelope (SASE), stamped self-addressed envelope (SSAE), or stamped addressed envelope (SAE) is an envelope with the sender's name...

In mathematics, the lower envelope or pointwise minimum of a finite set of functions is the pointwise minimum of the functions, the function whose value...

In mathematics and economics, the envelope theorem is a major result about the differentiability properties of the value function of a parameterized optimization...

Stellar envelope may mean: The region of a star that transports energy from the stellar core to the stellar atmosphere Common envelope in a binary system...

In mechanical engineering, an envelope is a solid representing all positions which may be occupied by an object during its normal range of motion. Another...

Like mitochondria, chloroplasts have a double-membrane envelope, called the chloroplast envelope, but unlike mitochondria, chloroplasts also have internal...

balloon is a lighter-than-air aircraft consisting of a bag, called an envelope, which contains heated air. Suspended beneath is a gondola or wicker basket...

A building envelope or building enclosure is the physical separator between the conditioned and unconditioned environment of a building, including the...

A circumstellar envelope (CSE) is a part of a star that has a roughly spherical shape and is not gravitationally bound to the star core. Usually circumstellar...

The Gaza envelope (Hebrew: עוטף עזה, otef aza) encompasses the populated areas in the Southern District of Israel that are within 7 kilometres (4.3 mi)...

Envelope tracking (ET) describes an approach to radio frequency (RF) amplifier design in which the power supply voltage applied to the RF power amplifier...

altered by components such as filters, which cut or boost frequencies; envelopes, which control articulation, or how notes begin and end; and low-frequency...

A green envelope (Malay: sampul hijau or sampul duit raya) is a Malay adaptation of the Chinese red envelope custom. During the festival of Eid ul-Fitr...

inside without folding. As with the manila envelope, it is traditionally buff in color. The manila envelope, a close relative of the folder, often has...

A windowed envelope is a conventional envelope with a transparent (typically PET or BOPS Bi-oriented polystyrene plastic film) window to allow the recipient's...

wind, the lifting gas capsules are often protected by a more rigid outer envelope or an airframe, with other gasbags such as ballonets to help modulate buoyancy...

The Soleau envelope (French: Enveloppe Soleau), named after its French inventor, Eugène Soleau [fr], is a sealed envelope serving as proof of priority...