• enPR: splēn, IPA: /spliːn/

spleen

1. (anatomy, immunology) In vertebrates, including humans, a ductless vascular gland, located in the left upper abdomen near the stomach, which destroys old red blood cells, removes debris from the bloodstream, acts as a reservoir of blood, and produces lymphocytes.
2. (archaic, except in the set phrase "to vent one's spleen") A bad mood; spitefulness.
   • 1709, [Alexander Pope], An Essay on Criticism, London: Printed for W. Lewis […], published 1711, OCLC 15810849 ↗:

     In noble minds some dregs remain, / Not yet purged off, of spleen and sour disdain.

3. (obsolete, rare) A sudden motion or action; a fit; a freak; a whim.
   • 1593, [William Shakespeare], Venvs and Adonis, London: Imprinted by Richard Field, […], OCLC 837166078 ↗; Shakespeare’s Venvs & Adonis: […], 4th edition, London: J[oseph] M[alaby] Dent and Co. […], 1896, OCLC 19803734 ↗:

     A thousand spleens bear her a thousand ways.

     Brief as the lightning in the collied night; That, in a spleen, unfolds both heaven and Earth

4. (obsolete) Melancholy; hypochondriacal affections.
   • 1712 May, [Alexander Pope], “The Rape of the Locke. An Heroi-comical Poem.”, in Miscellaneous Poems and Translations. By Several Hands, London: Printed for Bernard Lintott […], OCLC 228744960 ↗:

     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.

5. A fit of immoderate laughter or merriment.
   • c. 1601–1602, William Shakespeare, “Twelfe Night, or VVhat You VVill”, in Mr. William Shakespeares Comedies, Histories, & Tragedies: Published According to the True Originall Copies (First Folio), London: Printed by Isaac Iaggard, and Ed[ward] Blount, published 1623, OCLC 606515358 ↗, [Act III, scene ii]:

     By virtue, thou enforcest laughter ; thy silly thought, my spleen

• milt (now chiefly of animals); lien (uncommon)

• splenomegaly

• French: rate
• German: Milz
• Italian: milza, splene
• Portuguese: baço
• Russian: селезёнка
• Spanish: bazo

• French: spleen
• German: Groll, Trübsinn
• Portuguese: esplim
• Russian: хандра́
• Spanish: esplín

spleen (spleens, present participle spleening; past and past participle spleened)

1. (obsolete, transitive) To dislike.