adj. 1 powerful, strong, potent, influential, dominant, predominant, ascendant, weighty, doughty, authoritarian, autocratic, indomitable The pen is mightier than the sword He should have thought twice before challenging such a mighty opponent. 2 strong, muscular, powerful, robust, strapping, sturdy, brawny, burly, well-built, able-bodied, hardy, Colloq husky, hefty The smith a mighty man was he, With large and sinewy hands 3 big, large, huge, grand, great, enormous, gigantic, tremendous, towering, monumental, prodigious, massive, bulky The giant plucked a mighty tree from the earth and flung it across the sea
adv. 4 very, extremely It was mighty nice of you to visit me here in the Ozarks