Secondary

Secondary is an adjective meaning "second" or "second hand". It may refer to:

• Secondary (chemistry), term used in organic chemistry to classify various types of compounds
• The group of (usually at least four) defensive backs in gridiron football
• An obsolete name for the Mesozoic in geosciences
• The secondary winding, or the electrical or electronic circuit connected to the secondary winding in a transformer
• Secondary emission, the phenomenon where primary incident particles of sufficient energy, when hitting a surface or passing through some material, induce the emission of secondary particles
  • Secondary electrons, electrons generated as ionization products
• Secondary color, color made from mixing primary colors
• Secondary craters, often called "secondaries"
• Secondary consumers in ecology Trophic dynamics
• Secondary dominant in music
• Secondary education
  • Secondary school - The type of school at the secondary level of education
• Secondary market, an aftermarket where financial assets are traded
• Secondary mirror, second mirror element/focusing surface in a reflecting telescope
• Secondaries, the second-largest group of remiges (wing feathers), which attach to the inner lower arm

See also

• Primary (disambiguation)
• Second (disambiguation)