Definition of inadvertently adverb in Oxford Advanced Learner's Dictionary. Meaning, pronunciation, picture, example sentences, grammar, usage notes, synonyms and more. Inadvertently means in a way that is not intentional or accidental. Learn how to use this adverb with sentences and synonyms, and see translations in different languages. The meaning of INADVERTENT is unintentional. How to use inadvertent in a sentence. The Formation of Inadvertent INADVERTENT meaning: 1. not intentional: 2. not intentional: 3. done or happening unintentionally: . Learn more.