unfasten

/ʌnˈfɑːs(ə)n/

//ʌnˈfɑːs(ə)n// verb

By · According to Wiktionary data (CC BY-SA) ·

"unfasten" is a 8-letter English headword indexed on PlainSpell.

The verdict

“unfasten” is outside the top-ranked English vocabulary, used as a verb - the kind of word writers most often double-check.

Unranked
below top-frequency English
8
letters

According to Wiktionary data (CC BY-SA, analyzed May 6, 2026) - To detach from any connecting agency or link; to disconnect.

Key facts for unfasten
PropertyValue
Headwordunfasten
LanguageEnglish
Part of speechVerb
IPA/ʌnˈfɑːs(ə)n/
Letters8
Misspellings tracked0
Confusable pairs0
SourceWiktionary (kaikki.org)

Where “unfasten” sits in English frequency

unfasten falls outside the top-100,000 ranked English words, the long-tail zone of technical, archaic, or low-frequency vocabulary, exactly where readers second-guess spellings most.

Beyond rank #100,000. Source: FrequencyWords open word-frequency list.

Spelling & Dictionary Insight

The English entry for unfasten is 8 letters long, classified as a verb, and transcribed in the International Phonetic Alphabet as /ʌnˈfɑːs(ə)n/. It sits outside the most-frequent rank tiers, which is often why uncommon words generate more spelling variants per reader. Wiktionary records 2 distinct senses for this headword, so context determines which meaning a reader should apply.

Zero misspellings are on record for unfasten in our index, which points to an orthography that plays by predictable English rules. It is not paired with a close-neighbour confusable in our dataset, since nothing in our dataset looks or sounds close enough to cause mix-ups.

Etymologically, the entry records: From un- + fasten. The correct English form is unfasten, spelled U-N-F-A-S-T-E-N.

Definition

  1. 1
    To detach from any connecting agency or link; to disconnect.
  2. 2
    To come unloosed or untied.

Etymology

From un- + fasten.

Synonyms

undo

Antonyms

do upbuttonbutton uptie upzipzip up

This word in other languages

desabrochar(Español)défaire(Français)lösen(Deutsch)

Definitions, pronunciation, and etymology for this entry are drawn from Wiktionary via the kaikki.org structured extract (CC BY-SA). See the methodology for how each field is sourced and updated.

Frequently Asked Questions

How do you spell "unfasten"?
"unfasten" is spelled U-N-F-A-S-T-E-N. The IPA pronunciation is /ʌnˈfɑːs(ə)n/.
What does "unfasten" mean?
As a verb, "unfasten" means: To detach from any connecting agency or link; to disconnect.
How do you pronounce "unfasten"?
The IPA (International Phonetic Alphabet) transcription for "unfasten" is /ʌnˈfɑːs(ə)n/. Click the speaker icon on the pronunciation badge above to hear it spoken aloud where audio is available.
What is the origin of the word "unfasten"?
From un- + fasten. See the full etymology section above for more details.
Is PlainSpell free to use?
Yes, PlainSpell is a completely free word reference. You can look up definitions, pronunciations, confusable pairs, homophones, and spelling corrections across 5 languages without any sign-up or subscription.

Using “unfasten”

The practical upshot for anyone who landed here from a spell-check.

  • The one correct English spelling is U-N-F-A-S-T-E-N - every other letter order is a misspelling in standard orthography.
  • Say it as /ʌnˈfɑːs(ə)n/ (IPA); tap the speaker on the pronunciation badge to hear it where audio exists.
  • Browse more English words and confusable pairs in the same reference. English words
Data Source

Wiktionary (via kaikki.org), licensed under CC BY-SA & GFDL. Word ordering uses an open word-frequency list; misspelling variants are generated by edit-distance from the correct headword.

Source: Wiktionary (via kaikki.org) Structured Wiktionary extract

Source: FrequencyWords open word-frequency list FrequencyWords open word-frequency list