[ suhb ]
See synonyms for sub on
  1. a submarine.

  2. a substitute: We've got a sub in English this week because our teacher's home with the flu.

  1. a submarine sandwich.

  2. a submissive in a BDSM sexual encounter or relationship.

  3. a subcontractor.

  4. a sublieutenant.

  5. a subordinate.

  6. a subaltern.

  7. British. an advance against one's wages, especially one granted as a subsistence allowance.

  8. Photography. a substratum.

verb (used without object),subbed, sub·bing.
  1. to act as a substitute for another.

  2. to act as the submissive partner in a BDSM sexual encounter or relationship.

verb (used with object),subbed, sub·bing.
  1. Photography. to coat (a film or plate) with a substratum.

Origin of sub

By shortening of words prefixed with sub-

regional variation note For sub

3. See hero sandwich.

Other definitions for SUB (2 of 4)


  1. supplemental unemployment benefits.

Other definitions for sub- (3 of 4)


  1. a prefix occurring originally in loanwords from Latin (subject; subtract; subvert; subsidy); on this model, freely attached to elements of any origin and used with the meaning “under,” “below,” “beneath” (subalpine; substratum), “slightly,” “imperfectly,” “nearly” (subcolumnar; subtropical), “secondary,” “subordinate” (subcommittee; subplot).

  2. Chemistry.

    • a prefix indicating a basic compound: subacetate; subcarbonate; subnitrate.

    • a prefix indicating that the element is present in a relatively small proportion, i.e., in a low oxidation state: subchloride; suboxide.

Origin of sub-

<Latin, combining form representing sub (preposition); akin to Greek hypó;see hypo-

Other definitions for sub. (4 of 4)


  1. subordinated.

  2. subscription.

  1. substitute.

  2. suburb.

  3. suburban.

  4. subway. Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

How to use sub in a sentence

British Dictionary definitions for sub (1 of 3)


/ (sʌb) /

  1. short for several words beginning with sub-: See subaltern, subeditor, submarine, subordinate, subscription, substandard, substitute, substratum (def. 6)

  2. British informal an advance payment of wages or salary: Formal term: subsistence allowance

verbsubs, subbing or subbed
  1. (intr) to serve as a substitute

  2. (intr) informal to act as a substitute (for)

  1. British informal to grant or receive (an advance payment of wages or salary)

  2. (tr) informal short for subedit

  3. (tr) photog to apply a substratum to (a film or plate base)

British Dictionary definitions for sub- (2 of 3)


  1. situated under or beneath: subterranean

  2. secondary in rank; subordinate: subeditor

  1. falling short of; less than or imperfectly: subarctic; subhuman

  2. forming a subdivision or subordinate part of a whole: subcommittee

  3. (in chemistry)

    • indicating that a compound contains a relatively small proportion of a specified element: suboxide

    • indicating that a salt is basic salt: subacetate

Origin of sub-

from Latin sub

British Dictionary definitions for sub. (3 of 3)


abbreviation for
  1. subeditor

  2. subito (in music)

  1. subscription

  2. substitute

Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Scientific definitions for sub-


  1. A prefix that means “underneath or lower” (as in subsoil), “a subordinate or secondary part of something else” (as in subphylum.), or “less than completely” (as in subtropical.)

The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.