| fallacious(adjective, poor, absurd, irrational, unconvincing) |
| foolish(adjective, strange, crazy, insane, absurd) |
| hard to believe(expression, adjective, idiom) |
| impracticable(adjective, doubtful, unlikely, impossible) |
| incongruous(adjective, absurd) |
| invalid(adjective, poor, false, unreasonable, inadequate) |
| irrational(adjective, false, strange, crazy, unreasonable) |
| nonsensical(adjective, strange, crazy, insane, absurd) |
| obscure(adjective, likely, unlikely, unbelievable, improbable) |
| outlandish(adjective, hard, difficult, extraordinary, amazing) |
| poor(adjective, slight, flat, thin, false) |
| puzzling(adjective, likely, unlikely, unbelievable, improbable) |
| senseless(adjective, false, unreasonable, absurd, irrational) |
| slight(adjective, flat, poor, thin, inadequate) |
| suspicious |
| thick(adjective, great, flat, poor, thin) |
| silly(adjective, absurd, excessive, expensive, steep) |
| anachronistic(adjective, absurd) |
| bizarre(adjective, strange, fantastic, doubtful, dubious) |
| faint(doubtful, dubious, improbable) |