"improbable" in the adjective sense
1. improbable, unlikely
not likely to be true or to occur or to have occurred
"legislation on the question is highly unlikely"
"an improbable event"
2. improbable, unbelievable, unconvincing, unlikely
having a probability too low to inspire belief
3. improbable, marvelous, marvellous, tall
too improbable to admit of belief
"a tall story"
Source: WordNet® (An amazing lexical database of English)
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