The Collaborative International Dictionary of English v.0.48:

Felt \Felt\, n. [AS. felt; akin to D. vilt, G. filz, and
   possibly to Gr. ? hair or wool wrought into felt, L. pilus
   hair, pileus a felt cap or hat.]
   1. A cloth or stuff made of matted fibers of wool, or wool
      and fur, fulled or wrought into a compact substance by
      rolling and pressure, with lees or size, without spinning
      or weaving.
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            It were a delicate stratagem to shoe
            A troop of horse with felt.           --Shak.
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   2. A hat made of felt. --Thynne.
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   3. A skin or hide; a fell; a pelt. [Obs.]
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            To know whether sheep are sound or not, see that the
            felt be loose.                        --Mortimer.
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   Felt grain, the grain of timber which is transverse to the
      annular rings or plates; the direction of the medullary
      rays in oak and some other timber. --Knight.
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