temperamental

temperamental /ˌtɛmprəˈmɛntl̟/ adjective
temperamental
/ˌtɛmprəˈmɛntl̟/
adjective
Britannica Dictionary definition of TEMPERAMENTAL
1 
[more temperamental; most temperamental]
a  : likely to become upset or angry
b  : unpredictable in behavior or performance
2 
: of or relating to someone's usual attitude, mood, or behavior

— temperamentally

adverb