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English definition of “AD”

AD

adverb uk   /ˌeɪˈdiː/ us  

AD adverb (CALENDAR)

abbreviation for Anno Domini: used in the Christian calendar when referring to a year after Jesus Christ was born: in 1215 AD/AD 1215 during the seventh century AD
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Years and yearly

AD

noun [U]

AD noun [U] (BRAIN DISEASE)

specialized medical abbreviation for Alzheimer's DiseaseMental and psychiatric disorders
(Definition of AD adverb, noun from the Cambridge Advanced Learners Dictionary & Thesaurus © Cambridge University Press)
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