Most mild-mannered is a term used to describe individuals who exhibit a composed, gentle, and moderate demeanor. Antonyms for this phrase could include words such as boisterous, rowdy, or aggressive. Boisterous describes individuals who are loud, energetic, and uncontrollable, while rowdy individuals are disorderly and disruptive. Aggressive individuals, on the other hand, are hostile and unyielding, commonly displaying hostile behavior or a confrontational attitude towards others. The antonyms for most mild-mannered are indicative of individuals who lack self-control, composure, and civility. These terms are a direct contrast to individuals who are most mild-mannered, emphasizing how the behavior and attitude of a person can significantly impact their social interactions.