1.(Anat.) A peculiar glandlike but ductless organ found near the stomach or intestine of most vertebrates and connected with the vascular system; the milt. Its exact function in not known.
2.Anger; latent spite; ill humor; malice; as, to vent one's spleen. "In noble minds some dregs remain, Not yet purged off, of spleen and sour disdain."
4.A sudden motion or action; a fit; a freak; a whim. (Obs. or R.) "A thousand spleens bear her a thousand ways."
5.Melancholy; hypochondriacal affections. "Bodies changed to various forms by spleen." "There is a luxury in self-dispraise: And inward self-disparagement affords To meditative spleen a grateful feast."
6.A fit of immoderate laughter or merriment. (Obs.) "Thy silly thought enforces my spleen."
...
