Which word means to soothe or pacify someone?

The word that means to soothe or pacify someone is "placate." This term is often used in contexts where someone is upset or angry, and taking steps to placate them involves calming their emotions and reducing their distress. To placate someone can involve actions or words that demonstrate understanding or offer reassurance, effectively mitigating their feelings of frustration or irritation.

In contrast, the other words do not convey the same meaning. "Perturb" suggests causing someone to feel anxious or unsettled, which is the opposite of soothing. "Agitate" means to disturb or excite, often in a negative way, further intensifying someone’s emotional state instead of calming it. "Encourage," while generally positive, does not specifically imply soothing; it is more about providing support or confidence rather than directly addressing someone's agitation or distress.