ଅର୍ଥ : Of or relating to the mental faculties.
ଅର୍ଥ : Able to exist under more than one set of conditions.
							ଉଦାହରଣ : 
							A facultative parasite can exist as a parasite or a saprophyte.
							
Restricted to a particular condition of life.
An obligate anaerobe can survive only in the absence of oxygen.ଅର୍ଥ : Granting a privilege or permission or power to do or not do something.
							ଉଦାହରଣ : 
							A facultative enactment.