i Register
In some senses, powerful is marked as archaic. Watch for register when choosing this word.
adj
Having, or capable of exerting, power or influence.
The powerful grace that lies / In herbs, plants, stones, and their true qualities.
[T]he ſubſtance of gold is indeed invincible by the povverfulleſt action of natural heat, […]
Leading to many or important deductions.
a powerful set of postulates
a powerful theorem
Large; capacious; said of veins of ore.
Being a powerful number.
adv
very; extremely
"She was stinkin' hot down here that summer, an' we were powerful dry."