Spleen
The spleen was an organ of the body that acted primarily as a blood filter.

in the mid-2260s, an experimental chemical stimulant designed to speed up reproduction and replacement of blood placed a tremendous strain on the patient's spleen and liver. ()

In 2268, Dr. Leonard McCoy suffered hemorrhage of the spleen after being tortured by the Vians. ()

In 2369, Captain Jean-Luc Picard suffered liver and spleen damage following an attack by Lenarians. ()

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Organs