| feeble(adjective, strong, weak, thin, frail) |
| unbelievable(adjective, weak, great, flat, poor) |
| weak(adjective, great, poor, thin, delicate) |
| incredible(adjective, great, flat, poor, thin) |
| implausible(adjective, weak, great, flat, poor) |
| improbable(adjective, great, flat, poor, thin) |
| flimsy(adjective, weak, poor, thin, unreasonable) |
| thin(adjective, weak, great, poor, delicate) |
| lame(adjective, weak, flat, poor, thin) |
| inconceivable(adjective, great, flat, poor, thin) |
| questionable(adjective, weak, great, flat, poor) |
| invalid(adjective, poor, inadequate, ineffective, ineffectual) |
| unlikely(adjective, extraordinary, strange, fantastic, doubtful) |
| unsubstantial(adjective, thin, extraordinary, strange, unreasonable) |
| poor(adjective, weak, flat, thin, delicate) |
| defective |
| doubtful(adjective, extraordinary, unreasonable, fantastic, dubious) |
| dubious(adjective, great, extraordinary, unreasonable, amazing) |
| groundless(poor, implausible, null and void) |
| inconclusive(adjective, weak, poor, thin, small) |