—adj. 1. next after the first in order, place, time, etc.
2. belonging or pertaining to a second order, division, stage, period, rank, grade, etc.
3. derived or derivative; not primary or original: secondary sources of historical research. 4. of minor or lesser importance; subordinate; auxiliary.
5. of or pertaining to secondary schools.
6. Chem. a. involving or obtained by the replacement of two atoms or groups.
b. noting or containing a carbon atom united to two other carbon atoms in a chain or ring molecule.
7. Elect.noting or pertaining to the current induced by a primary winding or to the winding in which the current is induced in an induction coil, transformer, or the like.
8. Geol.noting or pertaining to a mineral produced from another mineral by decay, alteration, or the like.
9. Gram. a. derived.
b. derived from a word that is itself a derived word: a secondary derivative. c. having reference to past time; noting or pertaining to a past tense: the Latin, Greek, or Sanskrit secondary tenses. Cf. primary (def. 13).
10. Ornith.pertaining to any of a set of flight feathers on the second segment of a bird's wing.
11. Ling.of, pertaining to, or characteristic of a secondary accent: secondary stress.
—n. 1. a person or thing that is secondary.
2. a subordinate, assistant, deputy, or agent.
3. Elect.a winding in a transformer or the like in which a current is induced by a primary winding.
4. Ornith.a secondary feather.
5. Football.the defensive unit that lines up behind the linemen.
6. Ling.See secondary accent.