noun
Abbreviation of submarine.
Clipping of submarine sandwich: a sandwich made on a long bun.
(nautical) Clipping of submersible.
(informal) Clipping of substitute, often in sports or teaching.
(British, informal, often in plural) Clipping of subscription (“a payment made for membership of a club, etc.”).
(Internet, informal) Clipping of subtitle
(computing, programming) Clipping of subroutine (sometimes one that does not return a value, as distinguished from a function, which does)
(colloquial) Clipping of subeditor
(colloquial) Clipping of subcontractor
(slang) Clipping of subwoofer
(publishing, colloquial) Clipping of submission (of a work for publication).
(BDSM, informal) Clipping of submissive
(colloquial, dated) Clipping of subordinate
(colloquial, dated) Clipping of subaltern
(colloquial, Internet) Clipping of subscription (or (by extension) a subscriber) to an online channel or feed.
(colloquial) Clipping of subsistence money, part of a worker's wages paid before the work is finished.
(Internet slang) Clipping of subreddit.
(Philippines, colloquial) Clipping of subject (“particular area of study”)
verb
(US, informal) To substitute for.
(US, informal) To work as a substitute teacher, especially in primary and secondary education.
(British, informal, soccer) To replace (a player) with a substitute.
(British, informal, soccer, less common, often as "sub on") To bring on (a player) as a substitute.
(British) 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.
preposition
Under.
verb
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.