improbable

adjectives

not likely to be true or to occur or to have occurred

"legislation on the question is highly unlikely"; "an improbable event"

improbable, unlikely

is derived from

is derived from

antonym

having a probability too low to inspire belief

is derived from

too improbable to admit of belief

"a tall story"

improbable, marvellous, marvelous, tall

is derived from