Used as a noun--you know what a noun is, don't you?
It means the name of anything.

Wight means a person--any creature.

Originally it meant a fairy, a supernatural being.

As an adjective it means brave, valiant, strong or powerful.

Or, it used to mean clever." "Oh, _you_! I hate the sight of you, you great bully!" Mary V ducked past him and ran.
"I'll help you look it up in the dictionary if you don't know how," Johnny called after her maliciously, not at all minding the epithet she had hurled at him.