powerful

Etymology

From Middle English pouerful, powarfull, equivalent to power + -ful.

adj

1. Having, or capable of exerting power, potency or influence.
   As soon as Julia returned with a constable, Timothy, who was on the point of exhaustion, prepared to give over to him gratefully. The newcomer turned out to be a powerful youngster, fully trained and eager to help, and he stripped off his tunic at once. 1963, Margery Allingham, chapter 19, in The China Governess
   Dear Political Activists All your chanting, marching, voting, picketing, boycotting and letter-writing will not change a thing; you will never right the wrongs of this world. The only thing your activity will accomplish is to make some of you feel better. Such activity makes powerless people feel useful, and provides them the illusion that they're making a difference. But it doesn't work. Nothing changes. The powerful keep the power. That's why they're called the powerful. 2004, George Carlin, “NOTHING CHANGES”, in When Will Jesus Bring the Pork Chops?, New York: Hyperion Books, →OCLC, →OL, page 106
2. Leading to many or important deductions.
   a powerful set of postulates
   a powerful theorem
3. (mining) Large; capacious; said of veins of ore.

adv

1. (Southern US) Synonym of very