obligate

1 of 2

verb

ob·​li·​gate ˈä-blə-ˌgāt 

obligated; obligating

transitive verb

1

: to bind legally or morally : constrain

You are obligated to repay the loan.

2

: to commit (something, such as funds) to meet an obligation

funds obligated for new projects

obligate

2 of 2

adjective

ob·​li·​gate ˈä-bli-gət  -blə-ˌgāt 

1

: restricted to one particularly characteristic mode of life

an obligate parasite

2

: biologically essential for survival

obligate mutualism

obligately adverb

Synonyms

Verb

• compel
• coerce
• force
• oblige

Examples of obligate in a Sentence

Verb

The contract obligates the firm to complete the work in six weeks.

the problem is of your own making, so don't think that you can obligate me to help

Recent Examples on the Web

Verb

The ethical rules prohibiting the practice were formally adopted in the 1980s by U.S. state bar associations, whose leaders feared that non-law-firm companies cared primarily about money and weren’t morally obligated to do right by the end client. —Jeff Kauflin, Forbes.com, 21 Aug. 2025

Given the break in the friendship, which was not our choice, are we obligated to send gifts? —Judith Martin, Mercury News, 15 Aug. 2025

Adjective

The results showed at least 12 separate origins of obligate myrmecophagy, with instances in each of the three main mammal groups: monotremes (egg-laying mammals), marsupials, and placentals. —Rupendra Brahambhatt, ArsTechnica, 20 Aug. 2025

The Antarctic midge, the continent’s sole native insect, was found to be the only organism to undergo both quiescence and obligate diapause. —Rafil Kroll-Zaidi, Harpers Magazine, 18 June 2025

Word History

Etymology

Verb

borrowed from Latin obligātus, past participle of obligāre "to tie up, restrain by tying, place under a legal or moral constraint" — more at oblige

Adjective

borrowed from German obligat "necessary, unavoidable," borrowed from Latin obligātus "under an obligation," from past participle of obligāre "to tie up, restrain by tying, place under a legal or moral constraint" — more at oblige

Note: In biological sense apparently adapted from use of German obligat by the mycologist Heinrich Anton de Bary (1831-88) in Vergleichende Morphologie und Biologie der Pilze, Mycetozoen und Bacterien (Leipzig, 1884), p. 382 ff.

First Known Use

Verb

1533, in the meaning defined at sense 1

Adjective

1887, in the meaning defined at sense 1

Rhymes for obligate

• abdicate
• abrogate
• acetate
• activate
• actuate
• adsorbate
• aggravate
• agitate
• alginate
• alienate
• allocate
• amputate

Kids Definition

obligate

verb

ob·​li·​gate

ˈäb-lə-ˌgāt

obligated; obligating

: to make (someone) do something by law or because it is right

Medical Definition

obligate

adjective

ob·​li·​gate ˈäb-li-gət  -lə-ˌgāt 

1

: restricted to one particularly characteristic mode of life or way of functioning

the infant is an obligate nose breather

—The Journal of the American Medical Association

an obligate parasite

2

: biologically essential for survival

obligate parasitism

obligately adverb

Legal Definition

obligate

transitive verb

ob·​li·​gate ˈä-blə-ˌgāt 

obligated; obligating

1

: to bind legally or morally

was obligated to pay child support

2

: to commit (as funds or property) to meet or provide security for an obligation

obligatory

ə-ˈbli-gə-ˌtōr-ē 

adjective