A Quick and Simple Dictionary

sub

1. Noun.  A submarine.
2. Noun.  A submarine sandwich—a sandwich made on a long bun.
3. Noun.  (US, informal) A substitute.
4. Noun.  (British, informal) A substitute in a football (soccer) game: someone who comes on in place of another player part way through the game.
5. Noun.  (British, informal) Short for subscription: a payment made for membership of a club, etc.
6. Noun.  (informal) A submissive in BDSM practices.
7. Noun.  (Internet, informal) Short for subtitle.
8. Noun.  (computing, programming) A subroutine (sometimes one that does not return a value, as distinguished from a function, which does).
9. Verb.  (US, informal) To substitute for.
10. Verb.  (US, informal) To work as a substitute teacher, especially in primary and secondary education.
11. Verb.  (British, informal) (football) To replace (a player) with a substitute.
12. Verb.  (British, informal) (football) Less commonly, and often as '''sub on''', to bring on (a player) as a substitute.
13. Verb.  (British) To perform the work of a subeditor or copy editor; to subedit.
14. Verb.  (UK, slang) To lend.
15. Preposition.  Under.
16. Verb.  To coat with a layer of adhering material; to planarize by means of such a coating.
17. Verb.  (microscopy) To prepare (a slide) with an layer of transparent substance to support and/or fix the sample.