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

• Secondary education
• A secondary consumer in an ecological sense.
• A Secondary dominant in music.
• The Secondary in American football refers to the group of (usually four) defensive backs.
• A Secondary functional group (or usually ion) attached to carbon atom connected to 2 other Carbon atoms in organic chemistry

See also

• In School Advertising
• Primary
• Tertiary
• Quaternary

Secundario ثانوی