The term "in nerves" typically refers to the state of being anxious, stressed, or on edge. There are several antonyms that can be used to describe the opposite of this feeling. For instance, one can use the term "calm" to describe someone who is not in nerves, or "relaxed" to refer to a state of tranquillity. Other antonyms that can be used in this context include "composed," "collected," "at ease," and "serene." These words are all similar in meaning, but each one conveys a slightly distinct flavor. Regardless of the specific word used, antonyms for "in nerves" describe a state of peace or contentment.