Adjective improbable has 3 senses
- improbable, unlikely - not likely to be true or to occur or to have occurred; "legislation on the question is highly unlikely"; "an improbable event"
Antonyms: probable, likely, plausible, presumed, presumptive, verisimilar, equiprobable
- improbable, unbelievable, unconvincing, unlikely - having a probability to low to inspire belief
Antonym: plausible (indirect, via implausible)
- improbable, marvelous, marvellous, tall - too improbable to admit of belief; "a tall story"
Antonyms: credible, believable (indirect, via incredible)
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