principal

noun

prin·​ci·​pal ˈprin(t)-s(ə-)pəl 

-sə-bəl

1

: a person who has controlling authority or is in a leading position: such as

a

: a chief or head man or woman

b

: the chief executive officer of an educational institution

c

: one who engages another to act as an agent subject to general control and instruction

specifically : the person from whom an agent's authority derives

d

: the chief or an actual participant in a crime

e

: the person primarily or ultimately liable on a legal obligation

f

: a leading performer : star

2

: a matter or thing of primary importance: such as

a(1)

: a capital sum earning interest, due as a debt, or used as a fund

(2)

: the corpus of an estate, portion, devise, or bequest

b

: the construction that gives shape and strength to a roof and is usually one of several trusses

broadly : the most important member of a piece of framing

principalship

ˈprin(t)-s(ə-)pəl-ˌship 

-sə-bəl-

noun

Synonyms of principal

• star

Examples of principal in a Sentence

the new high school principal

One of the principals in the assassination plot has been arrested.

Recent Examples on the Web

The principals of Midsummer bear more than a passing resemblance to the reality TV casts of the 21st century. —Literary Hub, 2 June 2026

Sadik-Khan is a principal at Bloomberg Associates and the former commissioner of the New York City Department of Transportation. —Time, 2 June 2026

The meeting occurred shortly after a Fort Worth school district principal was reassigned after old posts of hers surfaced on social media. —Ciara McCarthy, Fort Worth Star-Telegram, 2 June 2026

Manager Aaron Folbe and Underground principal Trevor Engelson will rep the filmmaker. —Aaron Couch, HollywoodReporter, 2 June 2026

Word History

Etymology

First Known Use

14th century, in the meaning defined at sense 1

Phrases Containing principal

• co-principal
• principal diagonal
• principal parts

Rhymes for principal

• principle

Kids Definition

principal

1 of 2 adjective

prin·​ci·​pal ˈprin(t)-s(ə-)pəl 

-sə-bəl

: most important : chief

the principal ingredient of the stew

principally

-ē 

prin(t)-splē

adverb

principal

2 of 2 noun

1

a

: a leading or most important person

b

: the head of a school

2

: a sum of money that is placed to earn interest, is owed as a debt, or is used as a fund

Legal Definition

principal

1 of 2 adjective

prin·​ci·​pal ˈprin-sə-pəl 

1

: being the main or most important, consequential, or influential

their principal place of business

the principal obligor

2

: of, relating to, or constituting principal or a principal

the principal amount of the loan

principal

2 of 2 noun

1

: a participant in an action or transaction especially having control or authority

the principals of a business

: as

a

: one who engages another to act for him or her subject to his or her general control or instruction : one from whom an agent derives authority to act compare fiduciary

b

: one who commits a crime or instigates, encourages, or assists another to commit it especially when constructively or actually present see also accessory sense 1

— principal in the first degree

: a principal under common law who intentionally commits and is actually or constructively present at the commission of a crime

— principal in the second degree

: a principal under common law who aids, encourages, or commands another to commit a crime and is actually or constructively present when it is committed

c

: the person primarily liable on a legal obligation or one who will ultimately bear the burden because of a duty to indemnify another as distinguished from one (as an endorser, surety, or guarantor) who is secondarily liable

2

: a capital sum earning interest, due as a debt, or used as a fund

shall receive the income from the trust until age 18, and thereafter the principal

payments shall be applied first to interest and then to principal

also : the main body of an estate, devise, or bequest