Antonyms of adj probative

1 sense of probative

Sense 1
probative, probatory -- (tending to prove a particular proposition or to persuade you of the truth of an allegation; "evidence should only be excluded if its probative value was outweighed by its prejudicial effect")

INDIRECT (VIA significant) -> insignificant, unimportant -- (devoid of importance, meaning, or force)

Similarity of adj probative

1 sense of probative

Sense 1
probative, probatory -- (tending to prove a particular proposition or to persuade you of the truth of an allegation; "evidence should only be excluded if its probative value was outweighed by its prejudicial effect")
       => significant (vs. insignificant), important -- (important in effect or meaning; "a significant change in tax laws"; "a significant change in the Constitution"; "a significant contribution"; "significant details"; "statistically significant")