light·less \ˈlītlə̇s\adjective Etymology: Middle English lihtles, lightles, from Old English lēohtlēas, from lēoht light + -lēas -less — more at light 1.: receiving no light : without illumination : dark < came up the lightless stairs — James Jones > 2.: giving no light < tells us of lightless stars, “visible” only to radio antennae — Scientific American Reader >