The Collaborative International Dictionary of English v.0.48:

Mossy \Moss"y\, a. [Compar. Mossier; superl. Mossiest.]
   1. Overgrown with moss; abounding with or edged with moss;
      as, mossy trees; mossy streams.
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            Old trees are more mossy far than young. --Bacon.
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   2. Resembling moss; as, mossy green.
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