1. to confirm or attest officially that something is true or meets certain standards
2. to guarantee or declare with confidence
3. to officially declare someone mentally ill or incompetent
Usage: legal/medical

Examples

• The doctor will certify that you are healthy enough to work.
• Please certify this document with your signature.
• The mechanic certified that the car was safe to drive.
• I can certify that she was present at the meeting.
• The school must certify all teachers before they can teach.
• The court certified him as mentally incompetent.
• This stamp certifies the authenticity of the artwork.