| suspect(adjective, weak, extraordinary, unreasonable, dubious) |
| unpersuasive(adjective, weak, poor, feeble, implausible) |
| erroneous(adjective, unpredictable, hollow, fickle, variable) |
| far-fetched(adjective, hard, extraordinary, fantastic, amazing) |
| fragile(adjective, weak, thin, delicate, shaky) |
| illogical(poor, fantastic, unbelievable, implausible, null and void) |
| inadequate(adjective, weak, poor, thin, delicate) |
| ineffective(adjective, weak, poor, inadequate, feeble) |
| insubstantial(adjective, weak, flat, poor, thin) |
| preposterous(adjective, extraordinary, fantastic, amazing, unbelievable) |
| shaky(adjective, weak, thin, frail, likely) |
| slight(adjective, weak, flat, poor, thin) |
| unimaginable(extraordinary, strange, amazing, doubtful, dubious) |
| unthinkable(extraordinary, strange, amazing, unbelievable, implausible) |
| wrong |
| fallacious(poor, implausible, null and void) |
| fantastic(adjective, extraordinary, strange, unlikely, unbelievable) |
| ineffectual(adjective, weak, poor, thin, delicate) |
| marvelous |
| open to doubt(expression, idiom, extraordinary, amazing, incredible) |