1. having no name known or acknowledged
2. done, made, or given by someone whose name is not known or not made public
3. lacking distinctive character or recognition

Examples

• The anonymous donor gave a million dollars to the charity.
• She received an anonymous letter in the mail.
• The witness chose to remain anonymous for safety reasons.
• He published his controversial article under an anonymous pseudonym.
• The anonymous tip led police to solve the case.
• Many anonymous buildings lined the busy street.
• The survey allowed for anonymous feedback from employees.