The Collaborative International Dictionary of English v.0.48:

Mighty \Might"y\, a. [Compar. Mightier; superl. Mightiest.]
   [AS. meahtig, mihtig; akin to G. m[aum]chtig, Goth. mahteigs.
   See Might, n.]
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   1. Possessing might; having great power or authority.
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            Wise in heart, and mighty in strength. --Job ix. 4.
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   2. Accomplished by might; hence, extraordinary; wonderful.
      "His mighty works." --Matt. xi. 20.
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   3. Denoting an extraordinary degree or quality in respect of
      size, character, importance, consequences, etc. "A mighty
      famine." --Luke xv. 14. "Giants of mighty bone." --Milton.
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            Mighty was their fuss about little matters.
                                                  --Hawthorne.
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