[ verb ob-li-geyt; adjective ob-li-git, -geyt ]
/ verb ˈɒb lɪˌgeɪt; adjective ˈɒb lɪ gɪt, -ˌgeɪt /

verb (used with object), ob·li·gat·ed, ob·li·gat·ing.

to bind or oblige morally or legally: to obligate oneself to purchase a building.
to pledge, commit, or bind (funds, property, etc.) to meet an obligation.


morally or legally bound; obliged; constrained.
necessary; essential.
Biology. restricted to a particular condition of life, as certain organisms that can survive only in the absence of oxygen: obligate anaerobe (opposed to facultative).

Origin of obligate

1400–50; late Middle English obligat (adj.) < Latin obligātus (past participle of obligāre to bind), equivalent to ob- ob- + ligātus; see ligate

Related forms

Can be confused

obligate oblige
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

Examples from the Web for obligating

British Dictionary definitions for obligating


/ (ˈɒblɪˌɡeɪt) /


to compel, constrain, or oblige morally or legally
(in the US) to bind (property, funds, etc) as security


compelled, bound, or restricted
biology able to exist under only one set of environmental conditionsan obligate parasite cannot live independently of its host Compare facultative (def. 4)

Derived Forms

obligable, adjectiveobligative, adjectiveobligator, noun

Word Origin for obligate

C16: from Latin obligāre to oblige
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Medicine definitions for obligating


[ ŏblĭ-gĭt, -gāt′ ]


Able to exist or survive only in a particular environment or by assuming a particular role.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.

Science definitions for obligating


[ ŏblĭ-gĭt, -gāt′ ]

Capable of existing only in a particular environment or by assuming a particular role. An obligate aerobe, such as certain bacteria, can live only in the presence of oxygen. An obligate parasite cannot survive independently of its host. Compare facultative.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.