{"era":"1940s","word":"plutonium","meaning":"radioactive element 94","children":[{"era":"1930","word":"Pluto","meaning":"outermost known planet at time of naming","children":[{"era":"classical","word":"Pluto","meaning":"god of the underworld","children":[{"era":"classical","word":"Plouton","meaning":"the wealthy one, lord of the dead","children":[{"era":"classical","word":"ploutos","meaning":"wealth, riches","children":[],"language":"Greek"}],"language":"Greek"}],"language":"Latin"}],"language":"Modern English"}],"language":"Modern English"}