Splanchnology - The study or discourse of the viscera (guts) - Greek: Splanchn(o), “viscera”.
Stomach (organ) - From Latin stomachus, “throat, gullet, stomach” [also “pride, indignation”, since those emotions were believed to arise from the stomach]. Derived from Greek stomachos, “throat, stomach”, literally an extension of stoma, "mouth, opening"
Pertaining to the stomach - Gastr(o)-, Ventr(o)-
Abdomen - “Belly fat”, from Latin abdomen, meaning, well, what it does today. Ultimate origin of the word is unknown.
Pertaining to the abdomen - Laparo-, Abdomin(o)-, Ventr(o)-
Digestion - From Latin dis-, “apart”, gerere, “to carry”, “to assimilate food in the bowels”
Pertaining to digestion - -pepsia
Lungs - From Old English lungen, from Proto-Germanic *lungw-, literally “the light organ”, legwh-, “not heavy, having little weight”. Probably from the fact that lungs float when put in water (and other organs do not).
Pertaining to the lungs - Pulmo-, Pneumo-
Liver - From Proto-Indo-European (PIE) *liep-, “to stick, adhere, fat”
Pertaining to the liver - Hepat(o)-, Hepatic, Jecor- (uncommon)
Pancreas - From Greek pankreas, "sweetbread", from pan-, “all”, and -kreas, “flesh”, presumably from the fleshy, uniform nature of the pancreas.
Pertaining to the pancreas - Pancrea-
Kidney - From Middle English kidenere, origin unknown. Possibly from cwið , “womb”, and ey, “egg”, for its shape.
Pertaining to the kidney - Nephro-, Ren(o)-
Intestines - From the Latin intestina, “inward, intestine”, from intus, “within, on the inside”. [Old English for the organ was hropp, “rope”]
Pertaining to the intestines - [Small intestine] Enter(o)-, Duoden-, Jejeun(o)- [Large intestine/Colon] Col(o)-, Sigmoid-
Spleen - From Greek splen, "the milt, spleen". From PIE *splegh-, “milt” [Note: “Milt” - fish sperm - got its name from the Proto-Germanic name for spleen, but the word once meant “guts” in general]
Pertaining to the spleen - Splen(o)-
Gall bladder - Gall from Old English galla, “gall, bile”, from PIE root *ghel- "yellowish green, gold". Bladder origin the same as urinary bladder.
Pertaining to the gall bladder - Cholecysto-, [Bile] Chol(e)-
Bladder - From Old English bledre, “urinary bladder, cystic pimple”, from PIE root *bhle-, "to blow" [same root as "blast"!]
Pertaining to the bladder - Vesic(o)-, Cyst(o)-
Learn more about medical and biological etymology on Biomedical Ephemera!
[Images from Historical Anatomies on the Web]
[Etymologies from Online Etymology Dictionary, who you should love and give money to]