how on earth

how on earth

An exclamation used to emphasize surprise, shock, anger, disgust, etc. How on earth did you get here? I thought your car was in the shop. Aw, how on earth did I get another dent in my bumper? How on earth did you sneak up on me like that!
See also: earth, how, on
Farlex Dictionary of Idioms. © 2015 Farlex, Inc, all rights reserved.
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References in classic literature ?
(which he didn't in the least believe), and how on earth the Doctor could have got to know of it--such bad luck!