Available Definitions:
1) a. - To make dark or black; to deprive of light; to obscure; as, a darkened room.
2) a. - To render dim; to deprive of vision.
3) a. - To cloud, obscure, or perplex; to render less clear or intelligible.
4) a. - To cast a gloom upon.
5) a. - To make foul; to sully; to tarnish.
6) v. i. - To grow or darker.