unthinkable
/ʌnˈθɪŋkəbəl/adjective, noun
unthinkable is spelled U-N-T-H-I-N-K-A-B-L-E: 11 letters and 4 syllables. It appears 1.9 times per million words in written English, the 20,356th most frequent word form (wordfreq, 2021 data). As an adjective, unthinkable means “That cannot be believed” (English Wiktionary, September 2026).
How many letters and syllables are in unthinkable?
| Letters | 11: U-N-T-H-I-N-K-A-B-L-E |
|---|---|
| Syllables | 4 (from its American pronunciation) |
| In writing | 1.9 times per million words; the 20,356th most frequent word form |
| Wrong spellings searched | none measured in search |
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).
How common is unthinkable?
Unthinkable appears 1.9 times per million words in written English, the 20,356th 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 unthinkable?
- /ʌnˈθɪŋkəbəl/
Unthinkable has 4 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: LL-Q1860_(eng)-Vealhurl-unthinkable.wav, Wikimedia Commons (author and licence on each file's page).
Forms of unthinkable
- more unthinkable comparative
- most unthinkable superlative
- uncountable
- unthinkables plural
Source: English Wiktionary, dump of September 2, 2026 (CC BY-SA 4.0), through kaikki.org (Wiktextract).
What does unthinkable mean?
The meanings the English Wiktionary records, quoted as written there (source below).
adjective
- 1
That cannot be believed.
Near-synonyms: unbelievable, incredible, inconceivable
- 2
Inconceivable or unimaginable; extremely improbable in a way that goes against common sense.
Near-synonyms: inconceivable, imponderable
- 3
Extremely improper; extremely at odds with norms of expected behavior.
Near-synonyms: taboo, unspeakable, unutterable, inconceivable
noun
- 1
Something, or various things collectively, that one dares not think about or do.
Near-synonym: unspeakable
Source: English Wiktionary, dump of September 2, 2026 (CC BY-SA 4.0), through kaikki.org (Wiktextract).
Unthinkable in Spanish, French, German and Portuguese
| Language | Words |
|---|---|
| French | incroyable , inconcevable, impensable, inimaginable |
| German | unvorstellbar , undenkbar |
| Portuguese | impensável |
| Spanish | impensable |
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 unthinkable come from?
From un- + think + -able.
Source: English Wiktionary, dump of September 2, 2026 (CC BY-SA 4.0), through kaikki.org (Wiktextract).