Mensa is an international organization that provides a platform for people with high IQs to connect and share ideas. The term 'IT HAS A TEST OF BRIGHTNESS' can be solved by the word Mensa, which is an acronym for the Latin phrase 'mensa et thoro, ' meaning 'mind and body.' Mensa is also known for its IQ test, which is used to measure intelligence and determine eligibility for membership in the organization.