corroborative
1. [ adjective ] serving to support or corroborate
Synonyms: confirmative confirming confirmatory corroboratory substantiating substantiative validating validatory verificatory verifying collateral
Examples:

"collateral evidence"

Related terms: supportive
Similar spelling:   corroborate
  corroborated
  corroboration
  corroborant
  corroboratory
  corporation
  corporation_law
  corporate_bond