From The Collaborative International Dictionary of English v.0.48 [gcide]:
Enlighten \En*light"en\, v. t. [Pref. en- + lighten: cf. AS.
inl[imac]htan. Cf. Enlight.]
1. To supply with light; to illuminate; as, the sun
enlightens the earth.
[1913 Webster]
His lightnings enlightened the world. --Ps. xcvii.
4.
[1913 Webster]
2. To make clear to the intellect or conscience; to shed the
light of truth and knowledge upon; to furnish with
increase of knowledge; to instruct; as, to enlighten the
mind or understanding.
[1913 Webster]
The conscience enlightened by the Word and Spirit of
God. --Trench.
[1913 Webster]
From WordNet (r) 3.0 (2006) [wn]:
enlighten
v 1: make understand; "Can you enlighten me--I don't understand
this proposal" [syn: enlighten, edify]
2: give spiritual insight to; in religion [syn: enlighten,
irradiate]
3: make free from confusion or ambiguity; make clear; "Could you
clarify these remarks?"; "Clear up the question of who is at
fault" [syn: clear, clear up, shed light on,
crystallize, crystallise, crystalize, crystalise,
straighten out, sort out, enlighten, illuminate,
elucidate]