definition of
powerful

[1] #1 powerful s. [knock-down] strong enough to knock down or overwhelm; "a knock-down blow". wn

[2] #2 powerful s. [brawny, hefty, muscular, sinewy] (of a person) possessing physical strength and weight; rugged and powerful; "a hefty athlete"; "a muscular boxer"; "powerful arms". wn

[3] #3 powerful r. [mighty, mightily, right] (Southern regional intensive) very; to a great degree; "the baby is mighty cute"; "he's mighty tired"; "it is powerful humid"; "that boy is powerful big now"; "they have a right nice place"; "they rejoiced mightily". wn

[4] #4 powerful s. [herculean] displaying superhuman strength or power; "herculean exertions". wn