pill bug

Any species of terrestrial crustacean in the genera Armadillidium and Armadillo (both in the order Isopoda), native to Europe and introduced worldwide. Pill bugs (sometimes called wood lice) resemble tiny armadillos in appearance and behaviour; they have a gray, oval body covered with platelike armour and, when disturbed, roll into a ball. They are about 0.75 in. (19 mm) long. Pill bugs live in dry, sunny places, in dry leaf litter, and on forest edges. Seealso sow bug.

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Common name for mifepristone, a drug used in the first several weeks of pregnancy for inducing abortion. RU-486 blocks the receptors for progesterone, a hormone necessary for the maintenance of pregnancy. The drug causes the breakdown of the uterine lining, which, along with the embryo, is shed through the vagina. It has been available in France for the termination of early pregnancy since 1988 and was approved for use in the U.S. in 2000. The name RU-486 is derived from the manufacturer Roussel-Uclaf and a serial number.

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Pill can refer to:

• A ball, or anything small and round, hence also:
• A pill (pharmacy): A pharmacological dosage form, now rendered obsolete by tablets and capsules, hence also:
• "The Pill", a general nickname for the combined oral contraceptive pill (e.g. "on the pill")
• American slang for recreationally used prescription drugs, particularly when used in plural (e.g. "popping pills")
• A tidal inlet on the coast, or a small creek of a river, hence:
• Various place names in England, especially in Somerset, such as:
• Huntspill, East Huntspill, West Huntspill
• Pill, Somerset
• A stake, stockade, stronghold or castle in the Welsh Language, hence:
• Various place names in Wales, such as:
• Pill, Pembrokeshire
• Pill, Swansea
• The inner city district of Pillgwenlly, Newport, South Wales
• Pill, Austria, the Tyrolean municipality
• "The Pill", a song by Loretta Lynn