| empty |
| enervated(adjective, dull, flat, low, sad) |
| fade |
| flat tire(expression, adjective, dull, flat, low) |
| flavorless(adjective, dull, weak, dead, tedious) |
| forlorn(adjective, dull, unhappy, dark, gloomy) |
| funereal(adjective, dull, unhappy, dark, gloomy) |
| gloomy(adjective, dull, unhappy, dark, miserable) |
| gradual(adjective, dull, moderate, low, stiff) |
| grim(adjective, dull, unhappy, dark, gloomy) |
| having spring fever(expression, adjective, idiom, dull, weary) |
| hebetudinous(adjective, dull, slow, heavy, stupid) |
| hindered(adjective, dull, moderate, low, stiff) |
| ho hum(expression, adjective, dull, weak, simple) |
| hypnotic(adjective, dull, quiet, slow, heavy) |
| idle(adjective, dull, heavy, weary, apathetic) |
| immobile(adjective, dull, idle, sluggish, lazy) |
| impassive(adjective, dull, simple, heavy, indifferent) |
| impeded(adjective, dull, moderate, low, stiff) |
| in holding pattern(expression, adjective, idiom, dull, idle) |