| ineffective(adjective, affect, useless, incompetent, unsound) |
| ineffectual(adjective, skill, affect, inadequate, feeble) |
| useless(adjective, wild, inferior, affect, inadequate) |
| bootless(adjective, inferior, inadequate, useless, trivial) |
| unavailing(adjective, inferior, inadequate, useless, trivial) |
| vain(adjective, inferior, inadequate, feeble, useless) |
| fruitless(adjective, inferior, inadequate, useless, trivial) |
| futile(adjective, inferior, inadequate, feeble, useless) |
| inefficient(adjective, weak, skill, inferior, affect) |
| inoperative(adjective, weak, skill, inferior, inadequate) |
| unsuccessful(adjective, inferior, inadequate, limited, feeble) |
| abortive(adjective, inferior, inadequate, useless, trivial) |
| dysfunctional(useless, unadaptive) |
| unproductive(adjective, inadequate, feeble, useless, trivial) |
| impotent(adjective, weak, skill, inferior, inadequate) |
| inadequate(adjective, skill, feeble, useless, unfit) |
| nugatory(adjective, inferior, inadequate, feeble, useless) |
| feckless(adjective, inferior, inadequate, limited, feeble) |
| worthless(adjective, inferior, inadequate, useless, trivial) |
| barren(adjective, inadequate, useless, trivial, unsound) |