insidiousness
noun
insidiousness is spelled I-N-S-I-D-I-O-U-S-N-E-S-S: 13 letters. It appears about once in every 55 million words in written English, the 231,291st most frequent word form (wordfreq, 2021 data). As a noun, insidiousness means “A surreptitious harmfulness, quality of entrapment, or treacherousness; the characteristic of being insidious” (English Wiktionary, September 2026). The plural of insidiousness is insidiousnesses.
How many letters and syllables are in insidiousness?
| Letters | 13: I-N-S-I-D-I-O-U-S-N-E-S-S |
|---|---|
| In writing | about once in every 55 million words; the 231,291st most frequent word form |
| Wrong spellings searched | none measured in search |
Sources: letters and syllables from the English Wiktionary's hyphenation or pronunciation; written frequency: wordfreq 3.1 (a 2021 snapshot of Wikipedia, subtitles, news, books, web text and social media).
How common is insidiousness?
Insidiousness appears about once in every 55 million words in written English, the 231,291st 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).
Forms of insidiousness
- insidiousnesses plural
Source: English Wiktionary, dump of September 2, 2026 (CC BY-SA 4.0), through kaikki.org (Wiktextract).
What does insidiousness mean?
The meanings the English Wiktionary records, quoted as written there (source below).
noun
- 1
A surreptitious harmfulness, quality of entrapment, or treacherousness; the characteristic of being insidious.
Source: English Wiktionary, dump of September 2, 2026 (CC BY-SA 4.0), through kaikki.org (Wiktextract).
Insidiousness in Spanish, French, German and Portuguese
In the sense the characteristic of being insidious:
| Language | Words |
|---|---|
| Spanish | insidia |
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 insidiousness come from?
From insidious + -ness.
Source: English Wiktionary, dump of September 2, 2026 (CC BY-SA 4.0), through kaikki.org (Wiktextract).