temperamental

/ˌtɛmpərəˈmɛntl/
adjective
  1. Having a tendency to change mood or behavior suddenly and unpredictably; easily upset or annoyed.
    • She can be temperamental, but her friends know she has a kind heart.
    • The old printer is temperamental and often jams in the middle of a job.
    • Our cat is very temperamental and sometimes refuses to eat for no reason.
  2. Relating to or caused by a person's natural character or disposition.
    • His temperamental shyness made it hard for him to speak in public.
    • Her temperamental optimism helped her stay positive during tough times.
    • The two siblings have temperamental differences that lead to frequent arguments.
Antonyms
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