The Collaborative International Dictionary of English v.0.48:

Goad \Goad\, n. [AS. g[=a]d; perh. akin to AS. g[=a]r a dart,
   and E. gore. See Gore, v. t.]
   A pointed instrument used to urge on a beast; hence, any
   necessity that urges or stimulates.
   [1913 Webster]

         The daily goad urging him to the daily toil.
                                                  --Macaulay.
   [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Goad \Goad\, v. t. [imp. & p. p. Goaded; p. pr. & vb. n.
   Goading.]
   To prick; to drive with a goad; hence, to urge forward, or to
   rouse by anything pungent, severe, irritating, or inflaming;
   to stimulate.
   [1913 Webster]

         That temptation that doth goad us on.    --Shak.

   Syn: To urge; stimulate; excite; arouse; irritate; incite;
        instigate.
        [1913 Webster]

WordNet (r) 3.0 (2006):

goad
    n 1: a pointed instrument that is used to prod into a state of
         motion [syn: prod, goad]
    2: a verbalization that encourages you to attempt something;
       "the ceaseless prodding got on his nerves" [syn: goad,
       goading, prod, prodding, urging, spur, spurring]
    v 1: give heart or courage to [syn: spur, goad]
    2: urge with or as if with a goad
    3: stab or urge on as if with a pointed stick [syn: goad,
       prick]
    4: goad or provoke,as by constant criticism; "He needled her
       with his sarcastic remarks" [syn: needle, goad]

Moby Thesaurus II by Grady Ward, 1.0:

104 Moby Thesaurus words for "goad":
   actuate, animate, assault, bear, bear upon, boost, buck, bull,
   bulldoze, bump, bump against, bunt, butt, butt against, cage,
   catalyst, coerce, compel, compulsion, corral, cram, crowd, desire,
   dig, drive, drive on, drove, egg on, elbow, exhort, flog, force,
   forward, gad, gadfly, give an impetus, give momentum, herd, hurtle,
   hustle, impel, impetus, impulse, impulsion, incentive, incitation,
   incite, incitement, instigate, jab, jam, jog, joggle, jolt, jostle,
   lash, lust, motivate, motivation, move, needle, nudge, oxgoad,
   passion, pile drive, poke, power, press, prick, prod, prompt,
   propel, punch, punch cattle, push, put in motion, ram, ram down,
   rattle, ride herd on, round up, rowel, run, run against,
   set agoing, set going, set in motion, shake, shepherd, shoulder,
   shove, sic, spur, stimulant, sting, stress, tamp, thrust, urge,
   whip, whip on, whiplash, wrangle, zeal



Easton's 1897 Bible Dictionary:

Goad
   (Heb. malmad, only in Judg. 3: 31), an instrument used by
   ploughmen for guiding their oxen. Shamgar slew six hundred
   Philistines with an ox-goad. "The goad is a formidable weapon.
   It is sometimes ten feet long, and has a sharp point. We could
   now see that the feat of Shamgar was not so very wonderful as
   some have been accustomed to think."

     In 1 Sam. 13:21, a different Hebrew word is used, _dorban_,
   meaning something pointed. The expression (Acts 9:5, omitted in
   the R.V.), "It is hard for thee to kick against the pricks",
   i.e., against the goad, was proverbial for unavailing resistance
   to superior power.