1. Serving to support or corroborate
   - collateral, confirmative, confirming, confirmatory, corroborative, corroboratory, substantiating, validating, validatory, verificatory, verifying

See also: substantiate, supportive

• Presidents' Day
• presidentship
• presiding officer
• presidio
• presidium
• presignify
• Presley
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• press of canvas
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