ETYM Cf. French secondaire, Latin secundaire. Related to Second.
1. Of second rank or importance or value; not direct or immediate.
2. Not of major importance.
3. Depending on or incidental to what is original or primary.
4. Belonging to a lower class or rank.
Of the stage of education and schools preceding collegiate; SYN. high.

The defensive football players who line up behind the linemen.