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pernicious

/pɚˈnɪʃəs/adjective

pernicious is spelled P-E-R-N-I-C-I-O-U-S: 10 letters and 3 syllables. It appears about once in every 1 million words in written English, the 34,063rd most frequent word form (wordfreq, 2021 data). As an adjective, pernicious means “Causing much harm in a subtle way” (English Wiktionary, September 2026).

How many letters and syllables are in pernicious?

Letters10: P-E-R-N-I-C-I-O-U-S
Syllables3 (from its American pronunciation)
In writingabout once in every 1 million words; the 34,063rd most frequent word form
Wrong spellings searchednone measured in search
Rhymes with
Same letters

Sources: letters and syllables from the English Wiktionary's hyphenation or pronunciation and the CMU Pronouncing Dictionary; written frequency: wordfreq 3.1 (a 2021 snapshot of Wikipedia, subtitles, news, books, web text and social media); rhymes and same-letter words are computed by PlainSpell from its own word list.

How common is pernicious?

Pernicious appears about once in every 1 million words in written English, the 34,063rd most frequent word form in the list.

Source: written frequency: wordfreq 3.1 (a 2021 snapshot of Wikipedia, subtitles, news, books, web text and social media).

How do you pronounce pernicious?

  • UK /pəˈnɪʃəs/
  • US /pɚˈnɪʃəs/

Pernicious has 3 syllables (counted from its American pronunciation in the CMU Pronouncing Dictionary).

Source: English Wiktionary, dump of September 2, 2026 (CC BY-SA 4.0), through kaikki.org (Wiktextract). Recordings: En-us-pernicious.ogg, Wikimedia Commons (author and licence on each file's page).

What rhymes with pernicious?

10 words on PlainSpell end in the same sounds as pernicious from its last stressed vowel (/ɪʃəs/):

Spelled with the same letters in another order: superionic.

Computed by PlainSpell from the pronunciations in the English Wiktionary (dump of September 2, 2026): a rhyme shares every sound from the last stressed vowel to the end; ordered by written frequency (wordfreq 3.1).

Forms of pernicious

  • more pernicious comparative
  • most pernicious superlative

Source: English Wiktionary, dump of September 2, 2026 (CC BY-SA 4.0), through kaikki.org (Wiktextract).

What does pernicious mean?

The meanings the English Wiktionary records, quoted as written there (source below).

adjective

  1. 1

    Causing much harm in a subtle way.

    pernicious influence

  2. 2

    Causing death or injury; deadly.

  3. 3

    Insidiously villainous: intending to cause harm, especially in a subtle way.

  4. 4

    obsoleteswift; celeritous.

Source: English Wiktionary, dump of September 2, 2026 (CC BY-SA 4.0), through kaikki.org (Wiktextract).

Pernicious in Spanish, French, German and Portuguese

LanguageWords
Frenchnocif, malsain, pernicieux (causing much harm), délétère, nuisible (causing death or injury)
Germanschädlich, bösartig, verderblich, perniziös (causing much harm), tödlich (causing death or injury)
Portuguesepernicioso (causing much harm), mórbido (causing death or injury)
Spanishpernicioso (causing much harm)

Source: English Wiktionary, dump of September 2, 2026 (CC BY-SA 4.0), through kaikki.org (Wiktextract). Translations are Wiktionary's, by sense; a linked word has its own PlainSpell page.

Where does pernicious come from?

From Middle English, from Old French pernicios, from Latin perniciōsus (“destructive”), from perniciēs (“destruction”), from per (“through”) + nex (“slaughter, death”).

Source: English Wiktionary, dump of September 2, 2026 (CC BY-SA 4.0), through kaikki.org (Wiktextract).

What to look up after pernicious