ENGLISH
REFERENCE

bac

n. uncountable
C1 Advanced bac

n. the amount of alcohol in a person's blood. It is a number used by doctors and police to see if someone is too drunk to drive safely.

n. the concentration of alcohol in the bloodstream, expressed as a percentage or mass per volume. Often used in legal and medical contexts to determine levels of intoxication.


SIMPLE

The driver had a high BAC after the party.

CONTEXTUAL

Police officers use breathalyzer tests to measure a driver's BAC during routine traffic stops.

COMPLEX

Legal limits for BAC vary by country, but even a small amount of alcohol can significantly impair the motor skills and reaction times necessary for operating a motor vehicle.

Usage

Typically used as an acronym for 'blood alcohol concentration'; often appears with the definite article 'the' or as a bare noun in technical reports.

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