1.Definition: lacking clarity or distinctness
"A dim figure in the distance"
2.Definition: lacking in light; not bright or harsh
"A dim light beside the bed"
3.Definition: made dim or less bright
"The dimmed houselights brought a hush of anticipation", "Dimmed headlights", "We like dimmed lights when we have dinner"
4.Definition: offering little or no hope
"Took a dim view of things"
5.Definition: slow to learn or understand; lacking intellectual acuity
"Never met anyone quite so dim"