| inadequate(adjective, limited, feeble, useless, inept) |
| inoperable(adjective, tired, impractical, hopeless, lost) |
| non-functioning |
| sterile(adjective, tired, over, lost, finished) |
| unavailing(adjective, weak, stupid, inferior, idle) |
| worthless(adjective, weak, stupid, inferior, inadequate) |
| dull(cold, sluggish, lifeless, lazy, inert) |
| flat |
| nugatory(adjective, inferior, inadequate, limited, feeble) |
| sluggish(calm, dull, gentle, lazy, inactive) |
| stagnant(calm, gentle, still, tired, inactive) |
| dud |
| duff |
| inefficient(weak, skill, inferior, inadequate, feeble) |
| low |
| malfunctioning |
| null(adjective, inferior, inadequate, limited, feeble) |
| null and void(expression, adjective, idiom, inferior, inadequate) |
| off(adjective, slight, remote, inactive, outside) |
| out of commission(expression, adjective, idiom, dull, weak) |