Definition of "spleen"
spleen
/spliːn/
noun
countable and uncountable, plural spleens
(archaic, except in the set phrase "to vent one's spleen") A bad mood; spitefulness.
(obsolete) Melancholy; hypochondriacal affections.
verb
third-person singular simple present spleens, present participle spleening, simple past and past participle spleened