obligation

American  

[ob-li-gey-shuhn] / ˌɒb lɪˈgeɪ ʃən /

noun

1. something by which a person is bound or obliged to do certain things, and which arises out of a sense of duty or results from custom, law, etc.

   Synonyms:

   responsibility

2. something that is done or is to be done for such reasons.

   to fulfill one's obligations.

3. a binding promise, contract, sense of duty, etc.

4. the act of binding or obliging oneself by a promise, contract, etc.

5. Law.

   1. an agreement enforceable by law, originally applied to promises under seal.

   2. a document containing such an agreement.

   3. a bond containing a penalty, with a condition annexed for payment of money, performance of covenants, etc.

   Synonyms:

   covenant, contract

6. any bond, note, bill, certificate, or the like, as of a government or a corporation, serving as evidence of indebtedness.

7. an indebtedness or amount of indebtedness.

8. a favor, service, or benefit for which gratitude is due.

9. a debt of gratitude.

   He felt an obligation to his teacher.

10. the state of being under a debt, as of gratitude, for a favor, service, or benefit.

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obligation British  

/ ˌɒblɪˈɡeɪʃən /

noun

1. a moral or legal requirement; duty

2. the act of obligating or the state of being obligated

3. law a legally enforceable agreement to perform some act, esp to pay money, for the benefit of another party

4. law

   1. a written contract containing a penalty

   2. an instrument acknowledging indebtedness to secure the repayment of money borrowed

5. a person or thing to which one is bound morally or legally

6. something owed in return for a service or favour

7. a service or favour for which one is indebted

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Synonym Usage

See duty.

Other Word Forms

• obligational
  adjective
• preobligation
  noun
• reobligation
  noun
• superobligation
  noun

Etymology

Origin of obligation

First recorded in 1250–1300; Middle English obligacioun, from Old French obligation, from Latin obligātiōn-, stem of obligātiō “bond, engagement, pledge,” from obligāt(us) “bound” (past participle of obligāre; see obligate) + -iō -ion

Explanation

An obligation is a duty. It's your obligation or responsibility to call your mom on Mother's Day. Sending flowers would be even better. When you are morally or legally bound to a particular commitment, it's your obligation to follow through on it. If you see a crime taking place, for example, it's your obligation to notify the police. If an elderly person comes onto a full bus, it's your obligation to give up your seat for him. Sometimes when you enter a formal agreement with someone involving money, you might have to sign an obligation that states you are committed to paying back what you've borrowed.

Example Sentences

Control of Islam’s holiest sites generates prestige and revenue, but it also carries an obligation to keep them safe and accessible for all Muslims.

From The Wall Street Journal • May 23, 2026

US Secretary of State Marco Rubio said on Thursday that the White House's preference was "a diplomatic solution" but added that Trump had the right and obligation to protect his country against any threat.

From BBC • May 22, 2026

A call option gives the holder the opportunity, but not the obligation, to buy a given stock at a stated price — known as the strike price.

From MarketWatch • May 19, 2026

That way, when the heirs inherit the highly appreciated stock, the cost basis will get reset to the current market value, effectively wiping out any capital-gains tax obligation on the assets up to that point.

From Barron's • May 16, 2026

With John to help with the planting and Mercy still sharing the work of the household, there was no obligation now to hold Kit to the tasks she hated.

From "The Witch of Blackbird Pond" by Elizabeth George Speare

Related Words

• accountability
• agreement
• bond
• burden
• commitment
• constraint
• contract
• debt
• duty
• liability
• necessity
• need
• promise
• requirement
• right
• trust
• understanding