411 REFERENCE · Wiktionary
Lord only knows
Reference material by Wiktionary contributors. This retains its source identity and is not 411 news reporting.
English
Phrase
phr ~know[s]
en God knows, in sense of something unknown to mortal men.
en 1882 w:David Ross Locke Nasby in Exile xix. 287 London has, heaven knows, enough homeless waifs, born the Lord only knows where, and brought up the Lord only knows how; but the London article is no more like the Parisian than chalk is like cheese.