One who, or that which, enlightens.

That can be enlightened.

plural of enlightenment

(history) A period of time ranging from part of the 17ᵗʰ century through much of the 18ᵗʰ century, characterized particularly by the importance of logic and reason.

(politics, philosophy) The policies of an absolute monarch who is influenced by the ideals of the Enlightenment.

(Buddhism) Buddha

Any of various strains of thought that arose in the late 18th and early 19th centuries in opposition to the 18th-century Enlightenment.

plural of Counter-Enlightenment

Synonym of benevolent tyrant

Synonym of enlightened absolutism