Abnormal cockatiel beak. different from…. . The meaning of ABNORMAL is deviating from the normal or average; often : unusual in an unwelcome or problematic way. They thought his behaviour was abnormal. Definition of abnormal adjective from the Oxford Advanced Learner's Dictionary. ab•nor•mal•ly, adv. How to use abnormal in a sentence. Synonyms for ABNORMAL: unusual, extraordinary, exceptional, unique, rare, uncommon, odd, outstanding; Antonyms of ABNORMAL: normal, common, ordinary, typical, usual, customary, unexceptional, unextraordinary. Sep 23, 2025 ยท abnormal (comparative more abnormal, superlative most abnormal) Not conforming to rule or system; deviating from the usual or normal type. [countable], pl. hbviqj 1q3 tlod 5ck9 som elflo c4tca rw8l c4cacd or