Nonadherence is a term that is used to describe a patient's failure to follow prescribed medical treatment properly. There are many synonyms for this term, all of which describe a similar concept. These include noncompliance, nonobservance, noncooperation, disobedience, neglect, and resistance. Each of these synonyms highlights a different aspect of the failure to adhere to treatment, such as neglecting to take medications, resisting the recommended treatment plan, or failing to follow through with follow-up appointments. While the reasons for nonadherence can vary, it is important for patients and healthcare providers to work together to address these issues and find solutions to ensure the best possible health outcomes for patients.