The word 'up-setting' is generally used to describe a state of emotional turmoil or agitation. Antonyms of the word would be terms that describe calmness or tranquility. Words such as peaceful, serene, composed, relaxed, and placid would be the opposites of the term. Other antonyms for 'up-setting' may include stable, steady, reassuring, unhurried, and untroubled. These words carry positive connotations and express stability, making them a good choice when attempting to convey the opposite of the word 'up-setting.' Overall, antonyms for 'up-setting' would be words that are suggestive of tranquility, equanimity, and peace.