obligate
ob·li·gate • v. / ˈäbliˌgāt/ 1. bind or compel (someone), esp. legally or morally: the medical establishment is obligated to take action in the best interest of the public.2. [tr.] commit (assets) as security: the money must be obligated within thirty days.• adj. / ˈäbligit/ Biol. restricted to a particular function or mode of life: an obligate intracellular parasite. Often contrasted with facultative.DERIVATIVES: ob·li·ga·tor / -ˌgātər/ n.
obligate
obligate (ob-lig-ayt) adj. describing an organism that is restricted to one particular way of life. Compare facultative.
obligate
obligate Applied to an organism that can survive only if a particular environmental condition is satisfied. For example, an obligate aerobe can survive only in the presence of air, an obligate parasite only in association with its host.