12-letter words that end in um
- mare clausum — a body of navigable water under the sole jurisdiction of a nation.
- mare crisium — (Sea of Crises) a dark plain in the first quadrant of the face of the moon: about 66,000 sq. mi. (170,000 sq. km).
- mare humorum — (Sea of Moisture) a dark plain in the third quadrant of the face of the moon: about 45,000 sq. mi. (117,000 sq. km).
- mare imbrium — (Sea of Showers) a dark plain in the second quadrant of the face of the moon: about 340,000 sq. mi. (880,000 sq. km).
- mare liberum — a body of navigable water to which all nations have unrestricted access.
- mare nostrum — our sea, especially the Mediterranean to the ancient Romans.
- mare sirenum — (Sea of Sirens) an area in the southern hemisphere of Mars, appearing as a dark region when viewed telescopically from the earth.
- mare undarum — (Sea of Waves) a dark plain in the first quadrant of the face of the moon: about 4800 sq. mi. (12,000 sq. km).
- mare vaporum — (Sea of Vapors) a dark plain in the first quadrant and near the center of the face of the moon: about 39,000 sq. mi. (101,000 sq. km).
- mesogastrium — the mesentery of the embryonic stomach.
- meum et tuum — mine and thine: used to express rights to property
- microscopium — a faint constellation in the S hemisphere lying near Sagittarius and Capricornus
- mycocecidium — a gall caused by a parasitic fungus.
- mycodomatium — an abnormal growth on a plant, caused by fungi
- neoytterbium — ytterbium.
- nielsbohrium — dubnium: symbol, Ns: the name originally proposed by Russian scientists for this element
- nonpetroleum — not containing any petroleum based substance
- nudum pactum — a simple contract or promise involving no legal considerations.
- original gum — See o.g (def 1).
- ornithogalum — any plant of the genus Ornithogalum
- paludamentum — a cloak worn by officials and military officers of ancient Rome, especially during wartime.
- panhellenium — an institution founded by the Roman Emperor Hadrian idealizing Greece's Classical history
- pax vobiscum — peace be with you
- pericementum — periodontal membrane.
- perichaetium — a leafy cluster (bracts) around the base of the reproductive organs of some plants, predominantly mosses
- perinephrium — the capsule of connective tissue that envelops the kidney.
- periodontium — the bone, connective tissue, and gum surrounding and supporting a tooth.
- perionychium — the epidermis surrounding the base and sides of a fingernail or toenail.
- periostracum — the external, chitinlike covering of the shell of certain mollusks that protects the limy portion from acids.
- periselenium — the closest point of the orbit of a spacecraft to the moon
- pityrosporum — a genus of fungi that live on the skin, esp that of the scalp and face, present in conditions such as dandruff and dermatitis
- pleiochasium — a flowering system in which several buds come out at the same time
- postliminium — postliminy.
- power vacuum — a situation when a government has no identifiable central authority
- praseodymium — a rare-earth, metallic, trivalent element, named from its green salts. Symbol: Pr; atomic weight: 140.91; atomic number: 59; specific gravity: 6.77 at 20°C.
- progymnasium — (in Europe) a school that prepares pupils for secondary education (the gymnasium)
- protactinium — a radioactive, metallic element. Symbol: Pa; atomic number: 91.
- prothalamium — prothalamion.
- pseudopodium — pseudopod.
- pygmy possum — any of various small Australasian marsupials, esp the burramys
- quadriennium — quadrennium.
- quadrominium — a building consisting of four individually owned apartments or living units.
- quinquennium — a period of five years.
- radiothorium — a disintegration product of thorium.
- receptaculum — a vessel, receptacle or container
- repositorium — a place for the storage of valuables, as in an ancient Roman temple or a church.
- salutatorium — a porch or room in a monastery or church serving as a meeting or almsgiving place for monks or priests and the laity.
- scribbly gum — any species of the genus Eucalyptus with smooth white bark marked with random patterns made by wood-boring insects
- serpentarium — a place where snakes are housed, especially for exhibition.
- sinus iridum — (Bay of Rainbows) a semicircular dark plain in the second quadrant of the face of the moon.