Antonyms of adj presumptive

2 senses of presumptive

Sense 1
presumptive -- (having a reasonable basis for belief or acceptance; "the presumptive heir (or heir apparent)")

INDIRECT (VIA probable) -> improbable, unlikely -- (not likely to be true or to occur or to have occurred; "legislation on the question is highly unlikely"; "an improbable event")

Sense 2
presumptive -- (affording reasonable grounds for belief or acceptance; "presumptive evidence"; "a strong presumptive case is made out")

INDIRECT (VIA credible) -> incredible, unbelievable -- (beyond belief or understanding; "at incredible speed"; "the book's plot is simply incredible")

Similarity of adj presumptive

2 senses of presumptive

Sense 1
presumptive -- (having a reasonable basis for belief or acceptance; "the presumptive heir (or heir apparent)")
       => probable (vs. improbable), likely -- (likely but not certain to be or become true or real; "a likely result"; "he foresaw a probable loss")

Sense 2
presumptive -- (affording reasonable grounds for belief or acceptance; "presumptive evidence"; "a strong presumptive case is made out")
       => credible (vs. incredible), believable -- (capable of being believed; "completely credible testimony"; "credible information")