The Collaborative International Dictionary of English v.0.48:

Sovereign \Sov"er*eign\ (? or ?; 277), a. [OE. soverain,
   sovereyn, OF. soverain, suvrain, F. souverain, LL. superanus,
   fr. L. superus that is above, upper, higher, fr. super above.
   See Over, Super, and cf. Soprano. The modern spelling
   is due to a supposed connection with reign.]
   1. Supreme or highest in power; superior to all others;
      chief; as, our sovereign prince.
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   2. Independent of, and unlimited by, any other; possessing,
      or entitled to, original authority or jurisdiction; as, a
      sovereign state; a sovereign discretion.
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   3. Princely; royal. "Most sovereign name." --Shak.
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            At Babylon was his sovereign see.     --Chaucer.
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   4. Predominant; greatest; utmost; paramount.
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            We acknowledge him [God] our sovereign good.
                                                  --Hooker.
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   5. Efficacious in the highest degree; effectual; controlling;
      as, a sovereign remedy. --Dryden.
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            Such a sovereign influence has this passion upon the
            regulation of the lives and actions of men. --South.
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   Sovereign state, a state which administers its own
      government, and is not dependent upon, or subject to,
      another power.
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