From Longman Dictionary of Contemporary EnglishHeaven/God/who/goodness knows!Heaven/God/who/goodness knows!a) used to say that you do not know the answer to a question ‘Where do you think he’s disappeared to this time?’ ‘God knows!’ Goodness knows why she didn’t go herself. b) used to emphasize a statement Goodness knows, I’ve never liked the woman, but I didn’t know how bad it would be to work with her. → know
