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

pestilent \pes"tilent\, a. l. pestilens, -entis, fr. pestis
   pest: cf. f. pestilent.
   pestilential; noxious; pernicious; mischievous. "corrupt and
   pestilent." --milton. "what a pestilent knave is this same"
   --shak.
   1913 webster

[2] : WordNet (r) 2.0

pestilent
     adj 1: exceedingly harmful syn: baneful, deadly, pernicious
     2: likely to spread and cause an epidemic disease; "a
        pestilential malignancy in the air"- jonathan swift;
        "plaguey fevers" syn: pestilential, pestiferous, plaguey
see also:
baneful deadly pernicious pestilential pestiferous plaguey 

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