obligatory

American  

[uh-blig-uh-tawr-ee, -tohr-ee, ob-li-guh-] / əˈblɪg əˌtɔr i, -ˌtoʊr i, ˈɒb lɪ gə- /

adjective

1. required as a matter of obligation; mandatory.

   A reply is desirable but not obligatory.

2. incumbent or compulsory (usually followed by on orupon ).

   duties obligatory on all.

   Synonyms:

   imperative, necessary

   Antonyms:

   voluntary

3. imposing moral or legal obligation; binding.

   an obligatory promise.

4. creating or recording an obligation, as a document.

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obligatory British  

/ ɒˈblɪɡətərɪ, -trɪ /

adjective

1. required to be done, obtained, possessed, etc

2. of the nature of or constituting an obligation

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Other Word Forms

• nonobligatorily
  adverb
• nonobligatory
  adjective
• obligatorily
  adverb
• obligatoriness
  noun
• unobligatory
  adjective

Etymology

Origin of obligatory

1425–75; late Middle English < Late Latin obligātōrius binding, equivalent to Latin obligā ( re ) to bind ( see obligate) + -tōrius -tory ¹

Explanation

Obligatory describes something you do because you have to, not because you want to. When you buy a car, you have to fill out the obligatory forms. In many homes, saying please and thank you is obligatory. Obligatory derives from the verb oblige, as in "after she was so nice, I felt obliged to take her a present." Some people feel burdened by lives of common obligation, giving presents, returning phone calls, eating birthday cake, attending religious services––none of which they feel any real desire to do.

Example Sentences

Rick Atkinson’s “The British Are Coming,” about the Revolutionary War, is beautifully written and started off with a bang, but soon the accounts of battles, with their obligatory suffering and death, became too much.

From The Wall Street Journal • Apr. 17, 2026

"But ultimately, any decision that the leadership of the revolution announces is obligatory and we will obey."

From Barron's • Apr. 9, 2026

In my experience, once you get past the now obligatory bot, getting in touch with an agent was quite fast — under five minutes.

From Salon • Mar. 13, 2026

She’s been with the company since and holds onto memories of touring and the obligatory “company meetings” that Berkett turned into surprise birthday celebrations for the dancers.

From Los Angeles Times • Mar. 12, 2026

These were the obligatory so-called Studienreisen, or study tours, their goal being the students’ acquisition of the necessary grounding in “the modern developments in Physics” that was simply unattainable in the United States.

From "Big Science" by Michael Hiltzik

Related Words

• compulsory
• de rigueur
• imperative
• mandatory
• requisite
• unavoidable