The Collaborative International Dictionary of English v.0.48:

Hoof \Hoof\, v. i.
   1. To walk as cattle. [R.] --William Scott.
      [1913 Webster]

   2. To be on a tramp; to foot. [Slang, U.S.]
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   To hoof it, to foot it.

   On the hoof, of cattle, standing (on the hoof); not
      slaughtered.

   beef on the hoof, live cattle.
      [Webster 1913 Suppl.]

The Collaborative International Dictionary of English v.0.48:

Hoof \Hoof\ (h[=oo]f), n.; pl. Hoofs (h[=oo]fs), very rarely
   Hooves (h[=oo]vz). [OE. hof, AS. h[=o]f; akin to D. hoef,
   G. huf, OHG. huof, Icel. h[=o]fr, Sw. hof, Dan. hov; cf.
   Russ. kopuito, Skr. [,c]apha. [root]225.]
   1. The horny substance or case that covers or terminates the
      feet of certain animals, as horses, oxen, etc.
      [1913 Webster]

            On burnished hooves his war horse trode. --Tennyson.
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   2. A hoofed animal; a beast.
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            Our cattle also shall go with us; there shall not a
            hoof be left behind.                  --Ex. x. 26.
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   3. (Geom.) See Ungula.
      [1913 Webster]

WordNet (r) 3.0 (2006):

hoof
    n 1: the foot of an ungulate mammal
    2: the horny covering of the end of the foot in ungulate mammals
    v 1: walk; "let's hoof it to the disco" [syn: foot, leg it,
         hoof, hoof it]
    2: dance in a professional capacity