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

Joint Army-Navy Program The US Army`s Long Range Hypersonic Weapon (LRHW) also known as Dark Eagle and the US Navy`s Intermediate-Range Conventional Prompt Strike (IRCPS) programs utilize common sub-sytems. —Adityajadhav, Interesting Engineering, 14 May 2026

Around 5,000 people reside in the town, give or take the shifting sub-population of soldiers from the Japanese Self-Defense Forces who ship in and out for noisy munitions drills in the mountains nearby. —Leslie Felperin, HollywoodReporter, 13 May 2026

Verb

Canadian bacon can sub out for regular bacon. —The Washington Post, San Diego Union-Tribune, 13 May 2026

When Cameron came down with Covid in 2022, the group brought in original drummer Dave Krusen, multi-instrumentalist John Klinghoffer, and veteran Seattle musician Richard Stuverud to sub for him. —Andy Greene, Rolling Stone, 12 May 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