insidiously
/ɪnˈsɪdi.əsli/adverb
insidiously is spelled I-N-S-I-D-I-O-U-S-L-Y: 11 letters. It appears about once in every 8 million words in written English, the 85,266th most frequent word form (wordfreq, 2021 data). As an adverb, insidiously means “In an insidious manner” (English Wiktionary, September 2026).
How many letters and syllables are in insidiously?
| Letters | 11: I-N-S-I-D-I-O-U-S-L-Y |
|---|---|
| In writing | about once in every 8 million words; the 85,266th 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 insidiously?
Insidiously appears about once in every 8 million words in written English, the 85,266th 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 insidiously?
- /ɪnˈsɪdi.əsli/
Source: English Wiktionary, dump of September 2, 2026 (CC BY-SA 4.0), through kaikki.org (Wiktextract).
Forms of insidiously
- more insidiously comparative
- most insidiously superlative
Source: English Wiktionary, dump of September 2, 2026 (CC BY-SA 4.0), through kaikki.org (Wiktextract).
What does insidiously mean?
The meanings the English Wiktionary records, quoted as written there (source below).
adverb
- 1
In an insidious manner.
Source: English Wiktionary, dump of September 2, 2026 (CC BY-SA 4.0), through kaikki.org (Wiktextract).
Insidiously in Spanish, French, German and Portuguese
In the sense in an insidious manner:
| Language | Words |
|---|---|
| French | insidieusement |
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 insidiously come from?
From insidious + -ly.
Source: English Wiktionary, dump of September 2, 2026 (CC BY-SA 4.0), through kaikki.org (Wiktextract).