The Collaborative International Dictionary of English v.0.48:

Reign \Reign\ (r?n), v. i. [imp. & p. p. Reigned (r?nd); p.
   pr. & vb. n. Reigning.] [OE. regnen, reinen, OF. regner, F.
   r['e]gner, fr. L. regnare, fr. regnum. See Reign, n.]
   1. To possess or exercise sovereign power or authority; to
      exercise government, as a king or emperor;; to hold
      supreme power; to rule. --Chaucer.
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            We will not have this man to reign over us. --Luke
                                                  xix. 14.
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            Shall Banquo's issue ever
            Reign in this kingdom?                --Shak.
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   2. Hence, to be predominant; to prevail. "Pestilent diseases
      which commonly reign in summer." --Bacon.
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   3. To have superior or uncontrolled dominion; to rule.
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            Let not sin therefore reign in your mortal body.
                                                  --Rom. vi. 12.
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   Syn: To rule; govern; direct; control; prevail.
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