Definition of attire noun in Oxford Advanced Learner's Dictionary. Meaning , pronunciation, picture, example sentences, grammar, usage notes, synonyms and more. ATTIRE definition: 1. clothes, especially of a particular or formal type: 2. clothes, especially of a particular or…. Learn more. Attire definition: to dress, array, or adorn , especially for special occasions, ceremonials, etc.. See examples of ATTIRE used in a sentence. The meaning of ATTIRE is to put garments on : dress, array; especially : to clothe in fancy or rich garments. How to use attire in a sentence.