mine (n.1)youdaoicibaDictYouDict
"pit or tunnel in the earth for obtaining metals and minerals," c. 1300, from Old French mine "vein, lode; tunnel, shaft; mineral ore; mine" (for coal, tin, etc,), of uncertain origin, probably from a Celtic source (compare Welsh mwyn, Irish mein "ore, mine"), from Old Celtic *meini-. Italy and Greece were relatively poor in minerals, thus they did not contribute a word for this to English, but there was extensive mining from an early date in Celtic lands (Cornwall, etc.). From c. 1400 as "a tunnel under fortifications to overthrow them."
wishy-washy (adj.)youdaoicibaDictYouDict
1690s, "feeble or poor in quality," reduplication of washy "thin, watery." Meaning "vacillating" first recorded 1873.
polysaprobicyoudaoicibaDictYouDict
"Of, designating, or inhabiting an aquatic environment that is poor in dissolved oxygen and contains much chemically reducing decayed organic matter", 1920s. From poly- + saprobic, after German polysaprob; compare mesosaprobic, oligosaprobic.