sub

¹ American  

[suhb] / sʌb /

noun

1. a submarine.

2. a substitute.

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

3. a submarine sandwich.

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

5. a subcontractor.

6. a sublieutenant.

7. a subordinate.

8. a subaltern.

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

10. Photography. a substratum.

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verb (used without object)

subbed, subbing

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, subbing

1. Photography. to coat (a film or plate) with a substratum.

SUB ² American  

abbreviation

1. supplemental unemployment benefits.

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sub- ³ American  

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.

   1. a prefix indicating a basic compound.

      subacetate; subcarbonate; subnitrate.

   2. a prefix indicating that the element is present in a relatively small proportion, i.e., in a low oxidation state.

      subchloride; suboxide.

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sub. ⁴ American  

abbreviation

1. subordinated.

2. subscription.

3. substitute.

4. suburb.

5. suburban.

6. subway.

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sub- ¹ British  

prefix

1. situated under or beneath

   subterranean

2. secondary in rank; subordinate

   subeditor

3. falling short of; less than or imperfectly

   subarctic

   subhuman

4. forming a subdivision or subordinate part of a whole

   subcommittee

5. 1. indicating that a compound contains a relatively small proportion of a specified element

      suboxide

   2. indicating that a salt is basic salt

      subacetate

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sub ² British  

/ sʌb /

noun

1. short for several words beginning with sub- See subaltern subeditor submarine subordinate subscription substandard substitute substratum

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

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verb

1. (intr) to serve as a substitute

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

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

4. informal (tr) short for subedit

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

sub. ³ British  

abbreviation

1. subeditor

2. subito (in music)

3. subscription

4. substitute

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sub– Scientific  

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.)

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Regionalisms

See hero sandwich.

Etymology

Origin of sub¹

By shortening of words prefixed with sub-

Origin of sub-³

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

Example Sentences

All those moving parts for a player who only made it onto the park as a sub fielder while Australia were still mathematically alive, with Smith powerless to stop Sri Lanka and Pathum Nissanka's charge.

From BBC • Feb. 18, 2026

“In theory, the Navy could implement an overhaul work package in Australia and reduce the work needed when the sub returns home.”

From The Wall Street Journal • Feb. 8, 2026

“While the headline index is still at a level that historically has been consistent with weak sub 2% growth, growth has been stronger than implied by the index for the past three years.”

From Barron's • Feb. 3, 2026

You can go maximalist — an Alison Roman–style ham party, complete with pickled vegetables, fancy mustard and crusty bread — or you can go blissfully minimal with a giant sub sliced into generous hunks.

From Salon • Feb. 3, 2026

I got to my feet: minor spraining of the sub ... trans ... damn, what was that called?

From "The Name of the Wind" by Patrick Rothfuss