Added 9 October 2026 self-assurance noun Categories: Mind & IdeasObscure Words noun ! Definition from WordNet 3.1, Princeton University. More about self-assurance at Wordnik → Where our words come from → Freedom from doubt; belief in yourself and your abilities. his assurance in his superiority did not make him popular Related Words: self-confidenceconfidencesurenessassuranceauthorityassertivenessself-esteemtrustsecurityinsuranceself-assurednessconfidentness Back to today's word