The Collaborative International Dictionary of English v.0.48:

How \How\, adv. [OE. how, hou, hu, hwu, AS. h?, from the same
   root as hw[=a], hw[ae]t, who, what, pron. interrog.; akin to
   OS. hw[=o]w, D. hoe, cf. G. wie how, Goth. hw[=e] wherewith,
   hwaiwa how. [root]182. See Who, and cf. Why.]
   1. In what manner or way; by what means or process.
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            How can a man be born when he is old? --John iii. 4.
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   2. To what degree or extent, number or amount; in what
      proportion; by what measure or quality.
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            O, how love I thy law! it is my meditation all the
            day.                                  --Ps. cxix.
                                                  97.
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            By how much they would diminish the present extent
            of the sea, so much they would impair the fertility,
            and fountains, and rivers of the earth. --Bentley.
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   3. For what reason; from what cause.
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            How now, my love! why is your cheek so pale? --Shak.
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   4. In what state, condition, or plight.
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            How, and with what reproach, shall I return?
                                                  --Dryden.
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   5. By what name, designation, or title.
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            How art thou called?                  --Shak.
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   6. At what price; how dear. [Obs.]
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            How a score of ewes now?              --Shak.
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   Note: How is used in each sense, interrogatively,
         interjectionally, and relatively; it is also often
         employed to emphasize an interrogation or exclamation.
         "How are the mighty fallen!" --2 Sam. i. 27. Sometimes,
         also, it is used as a noun; -- as, the how, the when,
         the wherefore. --Shelley.
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               Let me beg you -- don't say "How?" for "What?"
                                                  --Holmes.
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