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

pest \pest\, n. l. pestis: cf. f. peste.
   1. a fatal epidemic disease; a pestilence; specif., the
      plague.
      1913 webster

            england's sufferings by that scourge, the pest.
                                                  --cowper.
      1913 webster

   2. anything which resembles a pest; one who, or that which,
      is troublesome, noxious, mischievous, or destructive; a
      nuisance. "a pest and public enemy." --south.
      1913 webster

[2] : WordNet (r) 2.0

pest
     n : a persistently annoying person syn: blighter, cuss, pesterer,
          gadfly
see also:
blighter cuss pesterer gadfly 

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

122 moby thesaurus words for "pest":
   affliction, aggravation, ambulatory plague, annoyance, annoyer,
   bad news, badgerer, bane, bedevilment, besetment, black death,
   black plague, blast, blight, bore, bother, botheration,
   bothersomeness, bubonic plague, bugbear, bully, burden,
   buttonholer, calamity, cancer, canker, cellulocutaneous plague,
   crashing bore, crushing burden, curse, death, defervescing plague,
   destruction, devilment, difficulty, disease, dogging, downer, drag,
   drip, dry rot, dryasdust, dusty, epidemic, epiphytotic, epizootic,
   evil, exasperation, flat tire, frightful bore, fungus, gadfly,
   glandular plague, grievance, harasser, harassment, harm, harrier,
   harrying, headache, heckler, hemorrhagic plague, hounding, humdrum,
   infliction, irritant, larval plague, mildew, mold, molestation,
   moth, moth and rust, murrain, must, nag, nemesis, nudnik, nudzh,
   nuisance, open wound, pandemia, pandemic, persecution, persecutor,
   pester, pesterer, pesthole, pestilence, pill, plague, plague spot,
   plaguer, pneumonic plague, premonitory plague, problem, proser,
   rot, running sore, rust, sadist, scourge, septicemic plague,
   siderating plague, smut, tease, teaser, thorn, torment, tormentor,
   trial, trouble, tuberculosis, twaddler, vexation, vexatiousness,
   visitation, wet blanket, white plague, woe, worm, worriment,
   worry

[4] : Virtual Entity of Relevant Acronyms (Version 1.9, June 2002)

pest
     parameter estimation by sequential testing
     
     

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