obligate🔊

(Canada, US, Scotland) To bind, compel, constrain, or oblige by a social, legal, or moral tie.

(Canada, US, Scotland) To cause to be grateful or indebted; to oblige.

(Canada, US, Scotland) To commit (money, for example) in order to fulfill an obligation.

(biology) Requiring a (specified) way of life, habitat, etc.

Indispensable; essential; necessary; obligatory; mandatory; unavoidably invoked.