Source : Webster's Revised Unabridged Dictionary (1913)

Jeer \Jeer\, v. i. [imp. & p. p. {Jeered}; p. pr. & vb. n.
   {Jeering}.] [Perh. a corrup. of cheer to salute with cheers,
   taken in an ironical sense; or more prob. fr. D. gekscheren
   to jeer, lit., to shear the fool; gek a fool (see 1st {Geck})
   + scheren to shear. See {Shear}, v.]
   To utter sarcastic or scoffing reflections; to speak with
   mockery or derision; to use taunting language; to scoff; as,
   to jeer at a speaker.

         But when he saw her toy and gibe and jeer. --Spenser.

   Syn: To sneer; scoff; flout; gibe; mock.

Jeering \Jeer"ing\, a.
   Mocking; scoffing. -- n. A mocking utterance. --
   {Jeer"ing*ly}, adv.

Source : WordNet®

jeering
     adj : abusing vocally; expressing contempt or ridicule; "derisive
           laughter"; "a jeering crowd"; "her mocking smile";
           "taunting shouts of `coward' and `sissy'" [syn: {derisive},
            {gibelike}, {mocking}, {taunting}]

jeering
     n : showing your contempt by derision [syn: {jeer}, {mockery}, {scoff},
          {scoffing}]