• pernicious •
Pronunciation: pêr-ni-shês • Hear it!Part of Speech: Adjective
Meaning: 1. Fatal or potentially fatal, as a pernicious disease. 2. Evil, insidious, spitefully destructive, as pernicious rumors.
Notes: The noun from today's adjective is perniciousness and the adverb, perniciously. This adjective is related to an old noun, pernicion "destruction, ruin", which hasn't been used much since the 18th century. A second adjective, pernicious "fast, rapid, swift", is so rare as to probably be obsolete. The same applies to its noun, pernicity. Using this adjective probably isn't worth the risk of its being confused with today's Good Word.
In Play: We should not lose sight of the association of this Good Word with death when we use it: "The toxic waste dump being planned for our neighborhood could have a pernicious influence on the air we breathe and the water we drink." However, as always, the death could be purely metaphorical: "Celia Fate's pernicious chicanery succeeded in getting her the promotion she wanted but seriously undermined our faith in the fairness of promotions here."
Word History: This Good Word comes to us courtesy of French, which lent us its pernicieux, the descendant of Latin perniciosus. This adjective came from the noun pernicies "destruction", based on per "through, thorough" + nex (nek-s-) "death" + a noun suffix. The oldest form of this root was PIE nek-/nok- "death", the same root shows in Greek nekros "corpse", found in the English borrowings necrosis "dead tissue" and necrology "obituary". The o-form turns up in Latin noxa "injury", at the root of English noxious and obnoxious. You might wonder how the drink of the gods could be associated with death. Well, the same root, nek-, appears in Greek nectar, borrowed as English nectar with a meaning far removed from death or perniciousness. However, it entered Greek meaning "that which overcomes death" from nek- "death" + tar- "pass over, overcome".