The opposite of "be infuriated" is to be calm, composed, and collected. There are several antonyms for the word "infuriated." These include the words tranquil, serene, peaceful, and unruffled. People who are tranquil are usually undisturbed by any situation, whereas those who are serene are extremely calm and untroubled. Peaceful people do not let anything disturb their peace of mind, while the unruffled individuals remain unaffected in stressful situations. Using these words can help express a more relaxed and peaceful tone in writing, and promote calm and composed behavior and attitude, even in challenging situations.