|—the internet domain name for|
|—the chemical symbol for|
|1.||Compare DC alternating current|
|5.||Companion of the Order of Australia|
|6.||VDQS vin de pays See vin de table appellation d'origine contrôlé the highest French wine classification; indicates that the wine meets strict requirements concerning area of production, strength, etc|
|7.||Aelodau'r Cynulliad: Member of the Assembly (that is, the National Assembly of Wales)|
|[(for sense 2) Latin: before Christ]|
|(in prescriptions) ante cibum|
|[Latin: before meals]|
Latin ante cibum (before a meal)
The symbol for the element actinium.
The symbol for actinium.
Abbreviation of alternating current
|actinium (āk-tĭn'ē-əm) Pronunciation Key
A silvery-white, highly radioactive metallic element of the actinide series that is found in uranium ores. It is about 150 times more radioactive than radium and is used as a source of alpha rays and neutrons. Its most stable isotope has a half-life of about 22 years. Atomic number 89; melting point 1,050°C (1,922°F); boiling point (estimated) 3,200°C (5,792°F); specific gravity (calculated) 10.07; valence 3. See Periodic Table.
Latin ante cibum (before meals)
(Ac), radioactive chemical element, in Group IIIb of the periodic table, atomic number 89. Actinium was discovered (1899) by Andre-Louis Debierne in pitchblende residues left after Pierre and Marie Curie had extracted radium and was also discovered (1902) independently by Friedrich Otto Giesel. A ton of pitchblende ore contains about 0.15 mg of actinium. The rare, silvery-white metal is highly radioactive, glowing blue in the dark
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