ac

before Christ (Latin)

n. radioactive metallic element (Chemistry)

organized division of soldiers

regulation of air humidity and temperature (i.e. in a building)

AC may refer to any of the following, broken down by subject area.
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.ac is the Internet country code top-level domain (ccTLD) for Ascension Island. It is administered by NIC.AC, a subsidiary of the Internet Computer Bureau based in the United Kingdom. Registration for this domain is open to anyone..ac is also a second level domain for academic establishments in a number of countries; see .ac (second level).Registrations of internationalized domain names are accepted according to the following instructions.
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Noun
1. an electric current that reverses direction sinusoidally; "In the US most household current is AC at 60 cycles per second"
(synonym) alternating current
(hypernym) electricity, electrical energy

Noun
1. a radioactive element of the actinide series; found in uranium ores
(synonym) actinium, atomic number 89
(hypernym) chemical element, element
(substance-holonym) uranium ore

AC, actinium, radioactive chemical element

v. increase, accrete, enlarge, add to; enhance, heighten, intensify