| impossible(adjective, unreasonable, dubious, unlikely, flimsy) |
| improbable(adjective, unreasonable, doubtful, dubious, unlikely) |
| by no means(expression, idiom) |
| doubtful(adjective, unreasonable, dubious, unlikely, flimsy) |
| dubious(adjective, unreasonable, doubtful, unlikely, flimsy) |
| fanciful(adjective, doubtful, unlikely, implausible) |
| far-fetched(doubtful, unlikely, unbelievable, implausible, improbable) |
| far out(expression, adjective, unreasonable, dubious, unlikely) |
| farfetched(adjective, unreasonable, dubious, unlikely, flimsy) |
| fishy(adjective, unreasonable, dubious, unlikely, flimsy) |
| flimsy(adjective, unreasonable, doubtful, dubious, unlikely) |
| for the birds(expression, adjective, idiom, unreasonable, dubious) |
| full of holes(expression, adjective, idiom, unreasonable, dubious) |
| hundred-to-one(doubtful, unlikely, implausible) |
| iffy(doubtful, unlikely, implausible) |
| implausible(adjective, doubtful, dubious, unlikely, unbelievable) |
| inconceivable(adjective, unreasonable, doubtful, dubious, unlikely) |
| incredible(adjective, unreasonable, doubtful, dubious, unlikely) |
| not expected(expression, doubtful, unlikely, implausible) |
| obscure(adjective, unreasonable, dubious, unlikely, flimsy) |