Secondary may refer to:
Science and nature
*
Secondary emission
In particle physics, secondary emission is a phenomenon where primary incident particles of sufficient energy, when hitting a surface or passing through some material, induce the emission of secondary particles. The term often refers to the emi ...
, of particles
**
Secondary electrons
Secondary electrons are electrons generated as ionization products. They are called 'secondary' because they are generated by other radiation (the ''primary'' radiation). This radiation can be in the form of ions, electrons, or photons with suffici ...
, electrons generated as ionization products
* The secondary winding, or the electrical or electronic circuit connected to the secondary winding in a
transformer
*
Secondary (chemistry), a term used in organic chemistry to classify various types of compounds
*
Secondary color, color made from mixing primary colors
*
Secondary mirror, second mirror element/focusing surface in a reflecting telescope
*
Secondary craters, often called "secondaries"
*
Secondary consumer
A carnivore , or meat-eater (Latin, ''caro'', genitive ''carnis'', meaning meat or "flesh" and ''vorare'' meaning "to devour"), is an animal or plant whose food and energy requirements derive from animal tissues (mainly muscle, fat and other sof ...
, in ecology
* An obsolete name for the
Mesozoic in geosciences
*
Secondary feathers
Flight feathers (''Pennae volatus'') are the long, stiff, asymmetrically shaped, but symmetrically paired pennaceous feathers on the wings or tail of a bird; those on the wings are called remiges (), singular remex (), while those on the tail ...
, flight feathers attached to the ulna on the wings of birds
Society and culture
*
Secondary (football)
In gridiron football, defensive backs (DBs), also called the secondary, are the players on the defensive side of the ball who play farthest back from the line of scrimmage. They are distinguished from the other two sets of defensive players, the ...
, a position in American football and Canadian football
*
Secondary dominant
A secondary chord is an analytical label for a specific harmonic device that is prevalent in the tonal idiom of Western music beginning in the common practice period: the use of diatonic functions for tonicization.
Secondary chords are a typ ...
in music
*
Secondary education, education which typically takes place after six years of primary education
**
Secondary school
A secondary school describes an institution that provides secondary education and also usually includes the building where this takes place. Some secondary schools provide both '' secondary education, lower secondary education'' (ages 11 to 14) ...
, the type of school at the secondary level of education
*
Secondary market
The secondary market, also called the aftermarket and follow on public offering, is the financial market in which previously issued financial instruments such as stock, bonds, options, and futures are bought and sold. The initial sale of the s ...
, an aftermarket where financial assets are traded
See also
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*
*
Second (disambiguation)
A second is the base unit of time in the International System of Units (SI).
Second, Seconds or 2nd may also refer to:
Mathematics
* 2 (number), as an ordinal (also written as ''2nd'' or ''2d'')
* Second of arc, an angular measurement unit, ...
*
Binary (disambiguation)
Binary may refer to:
Science and technology Mathematics
* Binary number, a representation of numbers using only two digits (0 and 1)
* Binary function, a function that takes two arguments
* Binary operation, a mathematical operation that t ...
*
Primary (disambiguation)
*
Tertiary (disambiguation)
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