1. Harmful or unfavorable; acting against one's interests
The adverse weather conditions delayed the construction project.
As condições climáticas adversas atrasaram o projeto de construção.
2. Opposing or contrary in direction or effect
The court ruled against him due to adverse evidence.
O tribunal decidiu contra ele devido às provas adversas.
3. Negative or detrimental, especially regarding health or medical outcomes
The patient experienced adverse reactions to the medication.
O paciente experimentou reações adversas ao medicamento.