Ac

AC acromioclavicular; air conduction; alternating current; anodal closure; aortic closure.

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Ac actinium.

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Ac

The symbol for the element actinium.

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ac

abbr.

Latin ante cibum (before a meal)

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Ac,

1 symbol for the element actinium.

2 abbreviation for acetyl (CH₃CO).

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AC,

1 abbreviation for alternating current.

2 abbreviation for accommodative convergence. See AC/A ratio.

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AC/A ratio,

(in ophthalmology) the proportion between accommodative convergence (AC) and accommodation (A), or the amount of convergence automatically resulting from the dioptric focusing of the eyes at a specified distance. The ratio of accommodative convergence to accommodation is usually expressed as the quotient of accommodative convergence in prism diopters divided by the accommodative response in diopters.

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AC/DC,

slang term for a person who is both heterosexual and homosexual. See also bisexual.

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actinium (Ac) [ak-tin´e-um]

a chemical element, atomic number 89, atomic weight 227. (See Appendix 6.)

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Ac

chemical symbol, actinium.