substantiative

Adj.

1.

substantiative - serving to support or corroborate; "collateral evidence" Synonyms: corroborative, corroboratory, substantiating, validating, validatory, verificatory, verifying, confirmative, confirmatory, confirming, collateral

collateral, confirmative, confirmatory, confirming, corroborative, corroboratory, substantiating, supportive, validating, validatory, verificatory, verifying