The Collaborative International Dictionary of English v.0.48:

Three-piled \Three"-piled`\, a.
   1. Having the quality of three-pile; best; most costly. [R.]
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            Thou art good velvet; thou 'rt three-piled piece.
                                                  --Shak.
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   2. Fig.: Extravagant; exaggerated; high-flown. "Three-piled
      hyperboles." --Shak.
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   3. Accustomed to wearing three-pile; hence, of high rank, or
      wealth. [Obs.] "Three-piled people." --Beau. & Fl.
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