1. Dark, dim, obscure, gloomy, murky refer to absence or insufficiency of light. Dark implies a more or less complete absence of light: a dark night. Dim implies faintness of light or indistinctness of form (resulting from the lack of light or from imperfect vision): a dim outline. Obscure implies dimness that may arise also from factors that interfere with light or vision: obscure because of haze. Gloomy means cloudy, ill-lighted, dusky: a gloomy hall. Murky implies a thick or misty darkness: murky water. 4. dusky, black. 12. recondite, abstruse.