(figurative) a course of action that is unproductive and offers no hope of improvement; "all the clues led the police into blind alleys"; "so far every road that we've been down has turned out to be a blind alley"
absolutely required and not to be used up or sacrificed
absolutely necessary; vitally necessary; "essential tools and materials"; "funds essential to the completion of the project"; "an indispensable worker"
being or relating to or containing the essence of a plant etc; "essential oil"
able to move freely in all directions; "an owl's versatile toe can move backward and forward"; "an insect's versatile antennae can move up and down or laterally"; "a versatile anther of a flower moves freely in the wind"
competent in many areas and able to turn with ease from one thing to another; "a versatile writer"
changeable or inconstant; "versatile moods"
having great diversity or variety; "his various achievements are impressive"; "his vast and versatile erudition"
a colorless nonflammable liquid used as a solvent for fats and oils; because of its toxicity its use as a cleaning fluid or fire extinguisher has declined