* If escalating means to increase in intensity or severity: The antonym could be deescalate, reduce, mitigate, diminish, alleviate, or ease.
* If escalating means to move to a higher level or stage: The antonyms could be de-escalate, retreat, withdraw, descend, lower, or refrain.
The best antonym will depend on the specific situation and the intended meaning of the word "escalate."