"Lord only knows" meaning in English

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          "word": "God knows"
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          "ref": "1882, David Ross Locke, Nasby in Exile, xix. 287:",
          "text": "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.",
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        "Alternative form of God knows, in sense of something unknown to mortal men."
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  "word": "Lord only knows"
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  "lang_code": "en",
  "pos": "phrase",
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