The Collaborative International Dictionary of English v.0.48:

Protector \Pro*tect"or\, n. [L.: cf. F. protecteur.]
   1. One who, or that which, defends or shields from injury,
      evil, oppression, etc.; a defender; a guardian; a patron.
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            For the world's protector shall be known. --Waller.
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   2. (Eng. Hist.) One having the care of the kingdom during the
      king's minority; a regent.
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            Is it concluded he shall be protector ! --Shak.
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   3. (R. C. Ch.) A cardinal, from one of the more considerable
      Roman Catholic nations, who looks after the interests of
      his people at Rome; also, a cardinal who has the same
      relation to a college, religious order, etc.
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   Lord Protector (Eng. Hist.), the title of Oliver Cromwell
      as supreme governor of the British Commonwealth
      (1653-1658).
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