sub

1 of 5

noun (1)

ˈsəb 

: substitute

sub

2 of 5

verb

subbed; subbing

intransitive verb

: to act as a substitute

transitive verb

1

British : to read and edit as a copy editor : subedit

2

: subcontract sense 1

sub

3 of 5

noun (2)

: submarine

sub

4 of 5

abbreviation

1

subaltern

2

subscription

3

subsidiary

4

suburb

sub-

5 of 5

prefix

1

: under : beneath : below

subsoil

subaqueous

2

a

: subordinate : secondary : next lower than or inferior to

substation

subeditor

b

: subordinate portion of : subdivision of

subcommittee

subspecies

c

: with repetition (as of a process) so as to form, stress, or deal with subordinate parts or relations

sublet

subcontract

3

: less than completely, perfectly, or normally : somewhat

subacute

subclinical

4

a

: almost : nearly

suberect

b

: falling nearly in the category of and often adjoining : bordering on

subarctic

Synonyms of sub

Noun (1)

• substitute
• replacement

Verb

• substitute

Noun (2)

• submarine
• hero

Examples of sub in a Sentence

Noun (1)

we had a sub in English today, so we didn't get our test results back

Verb

Smith subbed for Jones at halftime.

subbing in a Broadway play

Smith subbed Jones at halftime.

Noun (2)

we shared a tuna sub at lunch

Recent Examples on the Web

Noun

The board approved a proposal to transfer $10,000 to a sub-account for that project. —Noah Lyons, San Diego Union-Tribune, 25 Feb. 2026

And director Harry Lighton’s dom-sub dramedy romance Pillion finally crossed the $1 million threshold, earning itself a point. —Joe Reid, Vulture, 24 Feb. 2026

Verb

While the fries are a la carte, every burger does come with a half pickle that might just sub for a side for some. —Evan Grant, Dallas Morning News, 25 Feb. 2026

Rothrock, who subbed in just the eighth minute after Jordan Morris went down with an injury, assisted the Sounders’ opening goal in the 15th minute after a hustle play to keep the ball in play and a cross to Albert Rusnák. —Braidon Nourse, Denver Post, 23 Feb. 2026

Word History

Etymology

Prefix

Middle English, from Latin, under, below, secretly, from below, near, from sub under, close to — more at up

First Known Use

Noun (1)

1777, in the meaning defined above

Verb

1853, in the meaning defined at intransitive sense

Noun (2)

1913, in the meaning defined above

Phrases Containing sub

• sub-adolescent
• sub-agency
• sub-agent
• sub-allocate
• sub-allocation
• sub-aqua
• sub-area
• sub-audible
• sub-average
• sub-basement
• sub-basin
• sub-block
• sub-branch
• sub-caste
• sub-ceiling
• sub-cellar
• sub-chapter
• sub-chief
• sub-clan
• sub-cluster
• sub-code
• sub-collection
• sub-college
• sub-collegiate
• sub-colony
• sub-commission
• sub-component
• sub-county
• sub-cult
• sub-dean
• sub-decision
• sub-department
• sub-development
• sub-dialect
• sub-director
• sub-directory
• sub-discipline
• sub-district
• sub-economy
• sub-faculty
• sub-file
• sub-folder
• sub-fragment
• sub-frame
• sub-generation
• sub-genre
• sub-goal
• sub-government
• sub-industry
• sub judice
• sub-language
• sub-level
• sub-lot
• sub-manager
• sub-market
• sub-maximal
• sub-maximally
• sub-menu
• sub-minimal
• sub-minimum
• sub-minister
• sub-national
• sub-network
• sub-niche
• sub-optimal
• sub-optimally
• sub-optimization
• sub-optimize
• sub-optimum
• sub-organization
• sub-panel
• sub-par
• sub-paragraph
• sub-parallel
• sub-part
• sub-period
• sub-phase
• sub-process
• sub-product
• sub-project
• sub-rational
• sub rosa
• sub-Saharan
• sub-scale
• sub-science
• sub-sea
• sub-secretary
• sub-sector
• sub-segment
• sub-sentence
• sub-series
• sub-site
• sub-skill
• sub-society
• sub-specialist
• sub-specialization
• sub-specialize
• sub-specialty
• sub specie aeternitatis
• sub-state
• sub-stellar
• sub-system
• sub-task
• sub-test
• sub-theme
• sub-therapeutic
• sub-topic
• sub-treasury
• sub-trend
• sub-tribe
• sub-type
• sub-unit
• sub-variety
• sub-visible
• sub-visual
• sub-world
• sub-writer
• sub-zero
• sub-zone

Rhymes for sub

• bub
• club
• cub
• dub
• grub
• hub
• nub
• pub
• rub
• scrub
• shrub
• snub

Kids Definition

sub

1 of 4 noun

ˈsəb 

: substitute entry 1

sub

2 of 4 verb

subbed; subbing

: to act as a substitute

sub

3 of 4 noun

: submarine entry 2

sub-

4 of 4 prefix

1

: under : beneath : below

subsoil

subfreezing

2

a

: being at a lower rank or secondary level

substation

b

: division or lesser part of

subcommittee

subtopic

c

: involving a secondary stage or process

sublet

subcontract

3

: less than completely, perfectly, or typically : somewhat

subdominant

4

: bordering upon

subarctic

Etymology

Prefix

from Latin sub- "under, below"

Legal Definition

sub-

prefix

1

: under : beneath : below

substandard

2

a

: subordinate : secondary : next lower than or inferior to

subagent

b

: subordinate portion of : subdivision of

subchapter

subcommittee

c

: assigning to another by the same method

sublicense

subcontract