'obligate' definitions:

Definition of 'obligate'

(from WordNet)
adjective
Restricted to a particular condition of life; "an obligate anaerobe can survive only in the absence of oxygen" [ant: facultative]
verb
Force somebody to do something; "We compel all students to fill out this form" [syn: compel, oblige, obligate]
verb
Commit in order to fulfill an obligation; "obligate money"
verb
Bind by an obligation; cause to be indebted; "He's held by a contract"; "I'll hold you by your promise" [syn: oblige, bind, hold, obligate]

Synonyms of 'obligate'

From: Moby Thesaurus