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

pestiferous \pestif"erous\, a. l. pestiferus, pestifer;
   pestis pest + ferre to bear: cf. f. pestif`ere.
   1. pest-bearing; pestilential; noxious to health; malignant;
      infectious; contagious; as, pestiferous bodies. "poor,
      pestiferous creatures begging alms." --evelyn.
      "unwholesome and pestiferous occupations." --burke.
      1913 webster

   2. noxious to peace, to morals, or to society; vicious;
      hurtful; destructive; as, a pestiferous demagogue.
      1913 webster

            pestiferous reports of men very nobly held. --shak.
      1913 webster

[2] : WordNet (r) 2.0

pestiferous
     adj 1: contaminated with infecting organisms; "dirty wounds";
            "obliged to go into infected rooms"- jane austen syn:
             contaminated, dirty, infected
     2: likely to spread and cause an epidemic disease; "a
        pestilential malignancy in the air"- jonathan swift;
        "plaguey fevers" syn: pestilent, pestilential, plaguey
     3: tending to corrupt or pervert syn: corruptive, perversive
     4: 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,
         pesky, pestering, plaguy, plaguey, teasing, vexatious,
         vexing
see also:
contaminated dirty infected pestilent pestilential plaguey 
corruptive perversive annoying bothersome galling 
irritating nettlesome pesky pestering plaguy 
teasing vexatious vexing 

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

87 moby thesaurus words for "pestiferous":
   aggravating, annoying, bad, bad for, baneful, bothering,
   bothersome, catching, communicable, contagious, contaminated,
   deadly, destructive, disturbing, endemic, envenomed, epidemial,
   epidemic, epiphytotic, epizootic, exasperating, foul, galling,
   harassing, harmful, importunate, importune, infectious, infective,
   injurious, inoculable, insalubrious, insanitary, irking, irksome,
   irritating, malign, malignant, mephitic, miasmal, miasmatic,
   miasmic, morbific, noisome, noxious, pandemic, pathogenic, peccant,
   pesky, pestering, pestilent, pestilential, plaguesome, plaguey,
   plaguing, poisonous, polluted, provoking, septic, sporadic,
   spreading, tainted, taking, teasing, tiresome, tormenting, toxic,
   toxicant, toxiferous, troublesome, troubling, unhealthful,
   unhealthy, unhygienic, unsanitary, unwholesome, venenate,
   veneniferous, venenous, venomous, vexatious, vexing, virulent,
   wearisome, worrisome, worrying, zymotic

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