The definition of moody is someone who experiences wild shifts in emotions, often from happy to sad or nice to mean quickly or without reason.(adjective)
A person who has good moods and bad moods all the time is an example of someone who would be described as moody.
See moody in Webster's New World College Dictionary
See moody in American Heritage Dictionary 4
adjective mood·i·er, mood·i·est
, Helen Wills
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