Not bright or clear; lacking in light or illumination. The room was dim, with only a small lamp providing a faint glow.
Not clearly perceived or understood; vague. He had only a dim recollection of the events from last night.
Not very intelligent or quick to understand; dull-witted. Despite his dim reputation, he managed to solve the puzzle quickly.
Not strong or intense; faint or weak. There was a dim hope that the weather would clear up by the afternoon.