The Collaborative International Dictionary of English v.0.48:

ensign \en"sign\ ([e^]n"s[i^]n also [e^]n"s[imac]n, except for
   4a), n. [L. enseigne, L. insignia, pl. of insigne a
   distinctive mark, badge, flag; in + signum mark, sign. See
   Sign, and cf. Insignia, 3d Ancient.]
   1. A flag; a banner; a standard; esp., the national flag, or
      a banner indicating nationality, carried by a ship or a
      body of soldiers; -- as distinguished from flags
      indicating divisions of the army, rank of naval officers,
      or private signals, and the like.
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            Hang up your ensigns, let your drums be still.
                                                  --Shak.
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   2. A signal displayed like a standard, to give notice.
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            He will lift an ensign to the nations from far.
                                                  --Is. v. 26.
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   3. Sign; badge of office, rank, or power; symbol.
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            The ensigns of our power about we bear. --Waller.
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   4.
      (a) Formerly, a commissioned officer of the army who
          carried the ensign or flag of a company or regiment.
      (b) A commissioned officer of the lowest grade in the
          navy, corresponding to the grade of second lieutenant
          in the army. --Ham. Nav. Encyc.
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   Note: In the British army the rank of ensign was abolished in
         1871. In the United States army the rank is not
         recognized; the regimental flags being carried by a
         sergeant called the color sergeant.
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   Ensign bearer, one who carries a flag; an ensign.
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