Learn English – Is “I’m dead serious” formal

formality

In a movie I heard an actor saying "I'm dead serious". I looked up the dictionary and found that "dead" in this context means "really". Is it formal? Can we use it in business meetings?

Best Answer

Dead, as adverb, is informal when used to mean very, such as in "omelets are dead easy to prepare." (As far as I know, dead is used to mean very only in British English.)
When dead is used to mean absolutely, completely, exactly, straight, or directly it is not used only in informal phrases.