Definitions
1.nounA submarine.
2.nounA submarine sandwich: a sandwich made on a long bun."We can get subs at that deli."
3.nounA substitute, often in sports."She worked as a sub until she got her teaching certificate."
4.noun(often in plural) A subscription: a payment made for membership of a club, etc.
5.nounA subtitle."I've just noticed a mistake in the subs for this film."
6.nounA subroutine (sometimes one that does not return a value, as distinguished from a function, which does).
7.nounA subeditor.
8.nounA subcontractor.
9.noun(BDSM) A submissive.
10.nounA subordinate.
11.nounA subaltern.
12.nounA subscription (or (by extension) a subscriber) to an online channel or feed."I'm totally stoked; just got 10 new subs after my last video."
13.nounSubsistence money: part of a worker's wages paid before the work is finished.
14.verbTo substitute for.
15.verbTo work as a substitute teacher, especially in primary and secondary education.
16.verbTo replace (a player) with a substitute."He never really made a contribution to the match, so it was no surprise when he was subbed at half time."
17.verbLess commonly, and often as sub on, to bring on (a player) as a substitute."He was subbed on half way through the second half, and scored within minutes."
18.verbTo perform the work of a subeditor or copy editor; to subedit.
19.verbTo lend.
20.verbTo subscribe.
21.verb(BDSM) To take a submissive role.