| undefined(adjective, weak, obscure, dark, doubtful) |
| unlit(adjective, dull, soft, obscure, flat) |
| weaken(verb, dull, quiet, decline, fall) |
| achromatic(adjective, shabby, monotonous, distressed, neutral) |
| amorphous(adjective, unclear, indistinct, indistinguishable) |
| backward |
| blot(verb, dull, stain, discolor) |
| boorish(adjective, dull, slow, stupid, intelligent) |
| brain-dead(adjective, stupid) |
| camouflage(verb, cover, obscure, hide, conceal) |
| darkened(adjective, dull, dark, gloomy, black) |
| darkish(adjective, dull, obscure, dark, gloomy) |
| darksome |
| dull-witted |
| gloom(noun, verb, clear) |
| grey(adjective, overcast) |
| grimy(adjective, dull, soft, obscure, flat) |
| inky(adjective, dull, obscure, dark, gloomy) |
| low(adjective, dull, quiet, weak, simple) |
| lower(verb, reduce, diminish, obscure, hinder) |