| collateral(subject, minor, secondary, lesser) |
| contributory(subject, minor, collateral, secondary) |
| dejected(dull, quiet, gentle, restrained) |
| dispirited(adjective, dull, flat, sad) |
| down in the dumps(expression, adjective, idiom, dull, flat) |
| down in the mouth(expression, adjective, idiom, dull, quiet) |
| downcast(adjective, dull, quiet, gentle, flat) |
| downhearted(adjective, dull, flat, sad) |
| draggy(adjective, dull, flat, sad) |
| droopy(adjective, dull, flat, sad) |
| dull(adjective, calm, kind, smooth, soft) |
| flat(adjective, dull, quiet, kind, soft) |
| flat tire(expression, adjective, dull, flat) |
| ignoble(mean, inferior, compliant, obedient) |
| inanimate(adjective, dull, flat, sad) |
| indifferent(adjective, dull, quiet, flat) |
| languishing(adjective, dull, flat, sad) |
| lifeless(adjective, dull, quiet, flat) |
| lower(adjective, inferior, minor, secondary) |
| melancholic(adjective, dull, flat, sad) |