This article is from the the official alt.spleen FAQ, by Andrew Stellman with numerous contributions by others.
Andrew says: NOTE: PLEASE DO NOT SEND ANY MAIL TO ME REQUESTING MEDICAL ADVICE! I AM NOT A DOCTOR, AND WILL NOT GIVE YOU ANY USEFUL INFORMATION.
The easiest way to answer that question is to consult the dictionary:
Word SPLEEN (SPLEEN) n.
Definition --n. 1. a. One of the largest lymphoid structures in human
beings, a visceral organ composed of a white pulp of lymphatic
nodules and tissue and a red pulp of venous sinusoids in a
framework of fibrous partitions lying on the left side below the
diaphragm, functioning as a blood filter and to store blood. b.
A homologous organ or tissue in other vertebrates. 2. Obs. a.
The seat of emotions or passions. b. A whim; caprice. 3.
Archaic. Melancholy. 4. Ill temper.
spleeny --adj.
Etymology ME splene < OFr. esplen < Lat. splen < Gk splen.
Domain Everyday conversation
As everyone knows, the spleen is more than just a part of your lymphatic system. When properly cared for and coddled, a spleen can lead to a more fulfilling, and often more interesting life.
And, according to linguist Matthew Messner (mmdm@andrew.cmu.edu):
Word SPLENDID (SPLEHN'-did) Definition --adj. of, or pertaining to, the spleen.
 
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