Crepuscular and Lightless

Crepuscular adjective - Like twilight; dim.

Lightless and crepuscular are semantically related in dark topic. In some cases you can use "Lightless" instead an adjective "Crepuscular", when it comes to topics like lack of light, dark-hued.

Lightless adjective - Being without light or without much light.

Crepuscular and lightless are semantically related in dark topic. Sometimes you can use "Crepuscular" instead an adjective "Lightless", if it concerns topics such as lack of light, dark-hued.