Synonyms for Powerful:

adj.

able (adjective)
masterful, efficient, strong, effective.
able-bodied (adjective)
hearty, hardy, firm, stout, lusty.
acute (adjective)
fierce, severe, overpowering.
athletic (adjective)
brawny, active, muscular, able-bodied.
authoritative (adjective)
dictatorial, arrogant, autocratic, effective, impressive, authoritarian, imperious, influential, masterful, commanding, strong, authoritative, potent, effectual, important, consequential.
big (adjective)
consequential, valuable, leading.
brawny (adjective)
sinewy, hefty, athletic, husky, tough, vital.
burly (adjective)
big.
effective (adjective)
efficacious, convincing, persuasive, cogent.
energetic (adjective)
vivacious, fervid, peppy, mighty, spirited, driven, active, zealous, energetic, effervescent, puissant, vigorous, strong, forceful, mettlesome, potent, snappy, zippy, ardent, dynamic, spunky.
important (adjective)
high, big.
influential (adjective)
leading, masterful, motivational, commanding, authoritative, supreme, ruling, prejudicial, senior, important, influential, controlling, predominant.
persuasive (adjective)
convincing.
powerful (adjective)
commanding, competent, great, overpowering, high-powered, forceful, mighty, energetic, puissant, authoritative, vigorous, strong, potent, controlling, masterful.
strong (adjective)
stable, potent, strong, muscular, stalwart, mighty, vigorous, husky, sturdy, virile, mettlesome, firm, sinewy, vital, formidable, brawny, stout, robust, energetic, tough.
strong, effective (adjective)
efficacious, impressive, persuasive, compelling, forceful, cogent, forcible, authoritarian, dominant, puissant, controlling, paramount, robust, preeminent, ruling, mighty, influential, almighty, sturdy, competent, effectual, stalwart, convincing, energetic, vigorous, omnipotent, supreme, commanding, potent, dynamic, prevailing, all-powerful, authoritative, weighty.
vigorous (adjective)
fiery, strenuous, zestful, exuberant, active, spirited, peppy, enthusiastic, vigorous, virile, excited, passionate, energetic, lusty, zippy, frisky, full-blooded, dynamical, strong, eager, fervent, earnest, mettlesome, afire, emphatic, hearty, ardent, sprightly, ablaze, animated, puissant, lively, prolific, industrious, burning, zealous, agitated, impassioned, potent.

n.

severe, hardy, big, rugged, heavy, Hunky, able-bodied, hard, athletic. hard-hitting, helpful, functional, valuable, useful, operative, dynamic, worthwhile, efficient, practical, dynamical. heavily, lightly, full on the mouth/chin etc., fiercely, weighty, fierce, affect. odorless, laden, high, odoriferous, odorous, redolent. powerful (noun)
regent, sinewy, herculean, potent, muscular, coercive, right, ruling, cogent, puissant, mighty, omnipotent, knock-down, hefty, brawny, influential, reigning, compelling, almighty, all-powerful, superhuman, strong, regnant.

Other synonyms:

odorous, odoriferous, hard-hitting, odorless, stalwart, Hunky. hardy, dynamical, dominant, fiercely, laden, redolent. forcible, fierce. rugged. weighty, heavily. severe. lightly. heavy, hard. convincing
persuasive.
exalted
high.
fit
able-bodied.
muscular
athletic.
unconquerable
invincible.

Usage examples for powerful

  1. The effect of the sun in the open was powerful enough to make lead run like water. – Rip Foster in Ride the Gray Planet by Harold Leland Goodwin
  2. " It did use to smell powerful strong sometimes, lad, and many a time at first it turned me as sick as a youngster on his first v'yage; but I got accustomed to it after a bit. – A Chapter of Adventures by G. A. Henty
  3. The grasp was so firm, so powerful that the Vandal could not shake it off. – The Scarlet Banner by Felix Dahn