Abbreviation of submarine.
Short for submarine sandwich.: a sandwich made on a long bun.
(nautical) A submersible
(informal) Clipping of substitute., often in sports or teaching.
(Britain, informal, often in plural) A subscription: a payment made for membership of a club, etc.
(Internet, informal) A subtitle.
(computing, programming) A subroutine (sometimes one that does not return a value, as distinguished from a function, which does).
(colloquial) A subeditor.
(colloquial) A subcontractor.
(slang) A subwoofer.
(publishing, colloquial) A submission (of a work for publication).
(BDSM, informal) A submissive.
(colloquial, dated) A subordinate.
(colloquial, dated) A subaltern.
(colloquial, Internet) A subscription (or (by extension) a subscriber) to an online channel or feed.
(colloquial) Subsistence money: part of a worker's wages paid before the work is finished.
(Internet slang) Short for subreddit.
(US, informal) To substitute for.
(US, informal) To work as a substitute teacher, especially in primary and secondary education.
(Britain, informal, soccer) To replace (a player) with a substitute.
(Britain, informal, soccer, less common, often as "sub on") To bring on (a player) as a substitute.
(Britain) To perform the work of a subeditor or copy editor; to subedit.
(slang, Internet, transitive) To subtitle (usually a film or television program).
(UK, slang, transitive) To lend (a person) money.
(slang, intransitive) To subscribe.
(BDSM) To take a submissive role.
To coat with a layer of adhering material; to planarize by means of such a coating.
(microscopy) To prepare (a slide) with a layer of transparent substance to support and/or fix the sample.
Under.