The Collaborative International Dictionary of English v.0.48:

Forester \For"est*er\, n. [F. forestier, LL. forestarius.]
   1. One who has charge of the growing timber on an estate; an
      officer appointed to watch a forest and preserve the game.
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   2. An inhabitant of a forest. --Wordsworth.
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   3. A forest tree. [R.] --Evelyn.
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   4. (Zool.) A lepidopterous insect belonging to Alypia and
      allied genera; as, the eight-spotted forester (A.
      octomaculata), which in the larval state is injurious to
      the grapevine.
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