Source : Webster's Revised Unabridged Dictionary (1913)

Annoy \An*noy"\ ([a^]n*noi"), v. t. [imp. & p. p. {Annoyed}
   ([a^]n*noid"); p. pr. & vb. n. {Annoying}.] [OE. anoien,
   anuien, OF. anoier, anuier, F. ennuyer, fr. OF. anoi, anui,
   enui, annoyance, vexation, F. ennui. See {Annoy}, n.]
   To disturb or irritate, especially by continued or repeated
   acts; to tease; to ruffle in mind; to vex; as, I was annoyed
   by his remarks.

         Say, what can more our tortured souls annoy Than to
         behold, admire, and lose our joy?        --Prior.

   2. To molest, incommode, or harm; as, to annoy an army by
      impeding its march, or by a cannonade.

   Syn: To molest; vex; trouble; pester; embarrass; perplex;
        tease.

Annoying \An*noy"ing\, a.
   That annoys; molesting; vexatious. -- {An*noy"ing*ly}, adv.

Source : WordNet®

annoying
     adj : causing irritation or annoyance; "tapping an annoying rhythm
           on his glass with his fork"; "aircraft noise is
           particularly bothersome near the airport"; "found it
           galling to have to ask permission"; "an irritating
           delay"; "nettlesome paperwork"; "a pesky mosquito";
           "swarms of pestering gnats"; "a plaguey newfangled
           safety catch"; "a teasing and persistent thought
           annoyed him"; "a vexatious child"; "it is vexing to
           have to admit you are wrong" [syn: {bothersome}, {galling},
            {irritating}, {nettlesome}, {pesky}, {pestering}, {pestiferous},
            {plaguy}, {plaguey}, {teasing}, {vexatious}, {vexing}]

annoying
     n : the act of troubling or annoying someone [syn: {annoyance},
         {irritation}, {vexation}]