[1] : The Collaborative International Dictionary of English v.0.48

pesky \pes"ky\, a. etymol. uncertain.
   pestering; vexatious; troublesome. used also as an intensive.
   colloq.  low, u.s. --judd.
   1913 webster

[2] : WordNet (r) 2.0

pesky
     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: annoying, bothersome,
            galling, irritating, nettlesome, pestering, pestiferous,
            plaguy, plaguey, teasing, vexatious, vexing
     also: peskiest, peskier
see also:
annoying bothersome galling irritating nettlesome pestering 
pestiferous plaguy plaguey teasing vexatious 
vexing peskiest peskier 

[3] : Moby Thesaurus II by Grady Ward, 1.0

43 moby thesaurus words for "pesky":
   aggravating, annoying, awful, awfully, bothering, bothersome,
   damned, disturbing, dreadful, dreadfully, exasperating, extremely,
   galling, harassing, importunate, importune, irking, irksome,
   irritating, mean, monstrous, pestering, pestiferous, pestilent,
   pestilential, plaguesome, plaguey, plaguing, provoking, teasing,
   terribly, tiresome, tormenting, troublesome, troubling, troublous,
   ugly, vexatious, vexing, wearisome, wicked, worrisome, worrying

Pesky >> P Words
Pesky, definition of term: Pesky
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