compound

1 of 4

noun (1)

com·​pound ˈkäm-ˌpau̇nd 

1

: something formed by a union of elements or parts

especially : a distinct substance formed by chemical union of two or more ingredients in definite proportion by weight

a new antibiotic compound

2

a

: a word consisting of components that are words (such as rowboat, high school, devil-may-care)

b

: a word (such as anthropology, kilocycle, builder) consisting of any of various combinations of words, combining forms, or affixes

compound

2 of 4

verb

com·​pound käm-ˈpau̇nd 

kəm-ˈpau̇nd,

ˈkäm-ˌpau̇nd 

compounded; compounding; compounds

transitive verb

1

a

: to pay (interest) on both the accrued interest and the principal

b

: to add to : augment

compound an error

… had several other medical complications that compounded his condition.

—Jeffrey S. Hollis

2

: to form by combining parts

compound a medicine

3

: to put together (parts) so as to form a whole : combine

compound ingredients

… a thick sauce compounded of chilies, garlic, and ginger.

—Andy Birsh

4

a

: to settle amicably : adjust by agreement

b

: to agree for a consideration not to prosecute (an offense)

compound a felony

intransitive verb

1

: to become joined in a compound

2

: to come to terms of agreement

compounded with the enemy for peace

compoundable

käm-ˈpau̇n-də-bəl 

kəm-ˈpau̇n-

ˈkäm-ˌpau̇n-

adjective

compounder noun

compound

3 of 4

adjective

com·​pound ˈkäm-ˌpau̇nd  käm-ˈpau̇nd 

kəm-ˈpau̇nd

1

: composed of or resulting from union of separate elements, ingredients, or parts: such as

a

: having the blade divided to the midrib and forming two or more leaflets on a common axis

a compound leaf

b

: composed of united similar elements especially of a kind usually independent

a compound plant ovary

2

: involving or used in a combination

3

a

of a word : made by combining two or more words : constituting a compound (see compound entry 1 sense 2)

"Steamboat" is a compound noun.

b

of a sentence : having two or more main clauses

compound

4 of 4

noun (2)

com·​pound ˈkäm-ˌpau̇nd 

: a fenced or walled-in area containing a group of buildings and especially residences

a prison compound

an embassy compound

Synonyms

Noun (1)

• admixture
• alloy
• amalgam
• amalgamation
• blend
• cocktail
• combination
• composite
• conflation
• emulsion
• fusion
• intermixture
• meld
• mix
• mixture
• synthesis

Verb

• accelerate
• add (to)
• aggrandize
• amplify
• augment
• boost
• build up
• enlarge
• escalate
• expand
• extend
• hype
• increase
• multiply
• pump up
• raise
• stoke
• supersize
• swell
• up

Adjective

• amalgamated
• composite

Examples of compound in a Sentence

Noun (1)

mixed the chemicals together to form a new compound

The interest is compounded at regular intervals.

we compounded our error by waiting too long to call for help

Adjective

“Steamboat” is a compound noun.

“I told him to leave and he left” is a compound sentence.

Recent Examples on the Web

Noun

Just in the past week, however, Secretary of Health and Human Services Robert F. Kennedy, Jr., added additional items to the agenda, including a discussion of thimerosal—a mercury-containing compound that is used in some vaccines. —Tara Haelle, Scientific American, 25 June 2025

The boy's digestive system cannot tolerate lipids, which are fatty compounds or oils that are found in foods. —Peter Burke, FOXNews.com, 24 June 2025

Verb

Transnet’s problems have been compounded by the inefficiency of South Africa’s other major utility — the power company Eskom. —Alexander Onukwue, semafor.com, 25 June 2025

These effects can compound rapidly, creating cultural voids that are difficult to fill. —Tara Fitzpatrick-Navarro, Forbes.com, 25 June 2025

Adjective

The Impact To Expect From AI AI is poised to deliver over $40 billion in value industry-wide by 2033, with a compound annual growth rate (CAGR) of 38.1% between 2024 and 2033. —Tanya Fileva, Forbes.com, 27 June 2025

The global lawn and gardening consumables market size, valued at $23.10 billion in 2024, was forecast to grow at a compound annual growth rate of 4.3 percent from 2025 to 2030, according to a report by Grand View Research. —Soo Kim, MSNBC Newsweek, 26 June 2025

Word History

Etymology

Verb

Middle English compounen, from Anglo-French *cumpundre, from Latin componere, from com- + ponere to put — more at position

Adjective and Noun (1)

Middle English compouned, past participle of compounen — see compound entry 2

Noun (2)

by folk etymology from Malay kampung group of buildings, village

First Known Use

Noun (1)

1530, in the meaning defined at sense 2a

Verb

14th century, in the meaning defined at transitive sense 2

Adjective

14th century, in the meaning defined at sense 1

Noun (2)

1679, in the meaning defined above

Phrases Containing compound

• compound-complex
• compound eye
• compound fracture
• compound interest
• compound microscope
• compound number
• joint compound
• quaternary ammonium compound

Kids Definition

compound

1 of 4 verb

com·​pound käm-ˈpau̇nd 

kəm-;

ˈkäm-ˌpau̇nd

1

: to put together or be joined to form a whole : combine

2

: to form by combining parts

compound a medicine

3

: to settle or adjust by agreement

compound a debt

4

a

: to pay in the form of compound interest

interest compounded quarterly

b

: to add to

compounded our errors

compoundable

-ˈpau̇n-də-bəl 

-ˌpau̇n-

adjective

compounder noun

compound

2 of 4 adjective

com·​pound ˈkäm-ˌpau̇nd 

käm-ˈpau̇nd,

kəm-

1

: made of or by the union of separate elements or parts

a compound substance

2

: made up of two or more parts that are alike and form a common whole

a raspberry is a compound fruit

3

a

: being a word that is a compound

the compound noun "steamboat"

b

: consisting of two or more main clauses

"I told him to leave and he left" is a compound sentence

compound

3 of 4 noun

com·​pound ˈkäm-ˌpau̇nd 

1

: a word consisting of parts that are words

"rowboat," "high school," and "light-year" are compounds

2

: something formed by a union of elements or parts

especially : a distinct substance formed by the union of two or more chemical elements in definite proportion by weight

compound

4 of 4 noun

com·​pound ˈkäm-ˌpau̇nd 

: an enclosed area containing a group of buildings

Etymology

Verb

Middle English compounen "combine, compound," from early French compondre (same meaning), from Latin componere "compound, combine," from com- "with, together" and ponere "to place, put" — related to position

Noun

from a word in Malay, the language of the people of the Malay Peninsula, kampung "enclosure around a building"; both spelling and pronunciation influenced by the more familiar English word compound

Medical Definition

compound

1 of 3 transitive verb

com·​pound käm-ˈpau̇nd, kəm-ˈ, ˈkäm-ˌ 

: to form by combining parts

compound a medicine

compound

2 of 3 adjective

com·​pound ˈkäm-ˌpau̇nd, käm-ˈ, kəm-ˈ 

: composed of or resulting from union of separate elements, ingredients, or parts

a compound substance

compound glands

compound

3 of 3 noun

com·​pound ˈkäm-ˌpau̇nd 

: something formed by a union of elements or parts

specifically : a distinct substance formed by chemical union of two or more ingredients in definite proportion by weight

Legal Definition

compound

transitive verb

com·​pound kəm-ˈpau̇nd 

1

: to agree for a consideration not to prosecute (an offense)

Note: Compounding a felony is a common-law crime.

2

: to pay (interest) on both the accrued interest and the principal