The Collaborative International Dictionary of English v.0.48:

Hob \Hob\, n. [Prob. akin to hump. Cf. Hub. ]
   [1913 Webster]
   1. The hub of a wheel. See Hub. --Washington.
      [1913 Webster]

   2. The flat projection or iron shelf at the side of a fire
      grate, where things are put to be kept warm. --Smart.
      [1913 Webster]

   3. (Mech.) A threaded and fluted hardened steel cutter,
      resembling a tap, used in a lathe for forming the teeth of
      screw chasers, worm wheels, etc.
      [1913 Webster]

   4. A peg, pin, or mark used as a target in some games, as an
      iron pin in quoits; also, a game in which such a target is
      used.
      [Webster 1913 Suppl.]

The Collaborative International Dictionary of English v.0.48:

Hob \Hob\, n. [Orig. an abbrev. of Robin, Robert; Robin
   Goodfellow a celebrated fairy, or domestic spirit. Cf.
   Hobgoblin, and see Robin.]
   1. A fairy; a sprite; an elf. [Obs.]
      [1913 Webster]

            From elves, hobs, and fairies, . . .
            Defend us, good Heaven !              --Beau. & FL.
      [1913 Webster]

   2. A countryman; a rustic; a clown. [Obs.] --Nares.

The Collaborative International Dictionary of English v.0.48:

Hob \Hob\, n. (Zool.)
   The male ferret.
   [Webster 1913 Suppl.] Hobanob

The Collaborative International Dictionary of English v.0.48:

nave \nave\ (n[=a]v), n. [AS. nafu; akin to D. naaf, G. nabe,
   OHG. naba, Icel. n["o]f, Dan. nav, Sw. naf, Skr. n[=a]bhi
   nave and navel: cf. L. umbo boss of a shield. [root]260. Cf.
   Navel.]
   1. The block in the center of a wheel, from which the spokes
      radiate, and through which the axle passes; -- called also
      hub or hob.
      [1913 Webster]

   2. The navel. [Obs.] --hak.
      [1913 Webster]

WordNet (r) 3.0 (2006):

hob
    n 1: (folklore) a small grotesque supernatural creature that
         makes trouble for human beings [syn: goblin, hob,
         hobgoblin]
    2: (folklore) fairies that are somewhat mischievous [syn: elf,
       hob, gremlin, pixie, pixy, brownie, imp]
    3: a hard steel edge tool used to cut gears
    4: a shelf beside an open fire where something can be kept warm
    v 1: cut with a hob