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English definition of “lethal”

lethal

adjective uk   /ˈliː.θəl/ us  
C2 able to cause or causing death; extremely dangerous: Three minutes after the fire started, the house was full of lethal fumes. In the car the police found guns, knives, and other lethal weapons (= weapons which can kill). A 59-year-old man was executed by lethal injection (= by having a poisonous substance put into his body) this morning.informal That combination of tiredness and alcohol is lethal (= has a very bad effect).
lethally
adverb uk   /-i/ us  
(Definition of lethal from the Cambridge Advanced Learners Dictionary & Thesaurus © Cambridge University Press)
What is the pronunciation of lethal?
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