The term 'formally disavow' can be summarized as a synonym for the word 'ABJURE', which means to reject or renounce something formally or solemnly. This term is often used in legal contexts, such as when a witness in a court of law formally disavows any knowledge of a certain event or person. It can also be used in other contexts, such as when a political leader formally disavows a policy or statement made by another leader.