* Placate: To make someone less angry or upset; to appease or soothe.
* Miserable: Feeling or showing great unhappiness or discomfort.
The Connection: If someone is placated, they are no longer miserable. If someone is miserable, they are not placated.
Example:
* Placated: "The apology placated the angry customer."
* Miserable: "The child was miserable after losing his toy."
Note: While "miserable" is not a direct opposite of "placate" in the sense of being a formal antonym, they are conceptually linked as contrasting states of emotional well-being.