spleen: [13] Spleen comes via Old French esplen and Latin splēn from Greek splén, which may have been related to Latin liēn ‘spleen’ and Greek splágkhnon ‘entrails’ (source of English splanchnic ‘of the viscera’ [17]). In medieval physiology many internal organs were held to be the seat of a particular emotion, and the spleen was no exception. It had several conflicting states of mind attributed to it, but the one which survives is ‘moroseness’ or ‘bad temper’, in the derived adjective splenetic [16].
