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English definition of “deadly”

deadly

adjective uk   /ˈded.li/ us  

deadly adjective (VERY DANGEROUS)

B2 likely to cause death: a deadly virus a deadly weaponKillingMurder and attempted murder

deadly adjective (COMPLETE)

complete or extreme: They have been deadly enemies ever since Mark stole Greg's girlfriend.Very and extremeComplete and wholeIntensifying expressions

deadly adjective (BORING)

informal extremely boring: The party was deadly.Tedious and uninspiring

deadly

adverb uk   /ˈded.li/ us  
C1 completely or extremely: I thought she was joking but she was deadly serious.Very and extremeComplete and wholeIntensifying expressions
(Definition of deadly from the Cambridge Advanced Learners Dictionary & Thesaurus © Cambridge University Press)
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