Source : Webster's Revised Unabridged Dictionary (1913)

Herd \Herd\, a.
   Haired. [Obs.] --Chaucer.

Herd \Herd\, n. [OE. herd, heord, AS. heord; akin to OHG.
   herta,G. herde, Icel. hj["o]r?, Sw. hjord, Dan. hiord, Goth.
   ha['i]rda; cf. Skr. [,c]ardha troop, host.]
   1. A number of beasts assembled together; as, a herd of
      horses, oxen, cattle, camels, elephants, deer, or swine; a
      particular stock or family of cattle.

            The lowing herd wind slowly o'er the lea. --Gray.

   Note: Herd is distinguished from flock, as being chiefly
         applied to the larger animals. A number of cattle, when
         driven to market, is called a drove.

   2. A crowd of low people; a rabble.

            But far more numerous was the herd of such Who think
            too little and who talk too much.     --Dryden.

            You can never interest the common herd in the
            abstract question.                    --Coleridge.

   {Herd's grass} (Bot.), one of several species of grass,
      highly esteemed for hay. See under {Grass}.

Herd \Herd\, n. [OE. hirde, herde, heorde, AS. hirde, hyrde,
   heorde; akin to G. hirt, hirte, OHG. hirti, Icel. hir?ir, Sw.
   herde, Dan. hyrde, Goth. ha['i]rdeis. See 2d {Herd}.]
   One who herds or assembles domestic animals; a herdsman; --
   much used in composition; as, a shepherd; a goatherd, and the
   like. --Chaucer.

Herd \Herd\, v. i. [imp. & p. p. {Herded}; p. pr. & vb. n.
   {Herding}.] [See 2d {Herd}.]
   1. To unite or associate in a herd; to feed or run together,
      or in company; as, sheep herd on many hills.

   2. To associate; to ally one's self with, or place one's self
      among, a group or company.

            I'll herd among his friends, and seem One of the
            number.                               --Addison.

   3. To act as a herdsman or a shepherd. [Scot.]

Herd \Herd\, v. t.
   To form or put into a herd.

Source : WordNet®

herd
     n 1: a group of cattle or sheep or other domestic mammals all of
          the same kind that are herded by humans
     2: a group of wild animals of one species that remain together:
        antelope or elephants or seals or whales or zebra
     3: a crowd especially of ordinary or undistinguished persons or
        things; "his brilliance raised him above the ruck"; "the
        children resembled a fairy herd" [syn: {ruck}]

herd
     v 1: cause to herd, drive, or crowd together; "We herded the
          children into a spare classroom" [syn: {crowd}]
     2: move together, like a herd
     3: keep, move, or drive animals; "Who will be herding the
        cattle when the cowboy dies?"