Word Unit: Chemical Element: phosphorus (Greek: phosphoros, "light bringer", "morning star"; glows brightly because of rapid oxidation; nonmetal)
Word Unit: Chemical Element: platinum (Modern Latin: a diminutive of the Spanish plata, "silver", "platina"; metal)
Word Unit: Chemical Element: plutonium (Modern Latin: named for the planet Pluto; radioactive metal)
Word Unit: Chemical Element: polonium (Modern Latin: named by Murie Curie for her native Poland; radioactive metal)
Word Unit: Chemical Element: potassium (Modern Latin: named for potash, a compound of potassium; the symbol is from Latin kalium; from Arabic, gilf, and a reference to the charred ashes of the saltwort; metal)
Word Unit: Chemical Element: praseodymium (Greek: prasios, "green", plus didymos, "twin" [with the element neodymium] because of a green line in its spectrum; rare earth)
Word Unit: Chemical Element: promethium (Modern Latin: named for the Greek god Prometheus, who stole fire from heaven [the sun] for mankind; radioactive metal rare earth)
Word Unit: Chemical Element: protactinium (Modern Latin: some say it comes from Greek proto, "first"; plus actinium, "ray"; so, “first actinium”; radioactive metal)
Word Unit: Chemical Element: radium (Modern Latin: from Latin radius, meaning “ray”, because of its intense radioactivity; radioactive metal)
Word Unit: Chemical Element: radon (Modern Latin: from radium and argon, its chemical cousin; radioactive gas)
Word Unit: Chemical Element: rhenium (Modern Latin: from Latin Rhenus, in honor of the Rhine River in Germany; metal)
Word Unit: Chemical Element: rhodium (Modern Latin: from Greek, rhodon, "rose"; in reference to the red color of its salts; metal)
Word Unit: Chemical Element: roentgenium (Named for German physicist Wilhelm Conrad Roentgen)

Related "roentgen, x-ray" units: roentgeno-; Roentgen Biography.

Word Unit: Chemical Element: rubidium (Modern Latin: from Latin rubidus, "red"; from the red lines in its spectrum; metal)
Word Unit: Chemical Element: ruthenium (Modern Latin: named for Ruthenia [Latin for Russia] in the Urals, where one was first found; metal)
Word Unit: Chemical Element: rutherfordium (Modern Latin: named for Ernest Rutherford, a New Zealand physicist and chemist; radioactive metal)
Word Unit: Chemical Element: samarium (Modern Latin: named for a Scandinavian mineral samarskite; rare earth)
Word Unit: Chemical Element: scandium (Modern Latin: named for Scandinavia; metal)
Word Unit: Chemical Element: seaborgium (Modern Latin: named for Glenn Theodore Seaborg (1912-1999), an American nuclear physicist and Nobel Prize winner; radioactive metal)
Word Unit: Chemical Element: selenium (Modern Latin: from Greek, selene, the moon; nonmetal)

A cross reference of word units that are related, directly or indirectly, to the: "moon": Calendar, Moon Facts; Chemical Element: selenium; Gods and Goddesses; luna, luni-; Luna, the earth moon; menisc-; meno-; Planets in Motion; plano-; seleno-.