improbable

English

Etymology

Borrowed from Latin improbābilis. By surface analysis, im- +‎ probable.

Pronunciation

• (General American) IPA^(key): /ɪmˈpɹɑbəbl̩/
• (Received Pronunciation) IPA^(key): /ɪmˈpɹɒbəbl̩/

• Audio (UK):

  (file)

• Audio (US):

  (file)

• Hyphenation: im‧prob‧a‧ble

Adjective

improbable (comparative more improbable, superlative most improbable)

1. Not likely to be true.

   It's highly improbable that aliens abducted you.

   • 1598, John Florio, “Improbabile”, in A Worlde of Words, or Most Copious, and Exact Dictionarie in Italian and English, […], London: […] Arnold Hatfield for Edw[ard] Blount, →OCLC, page 171, column 1:

     Improbabile, that cannot be prooued, improbable.

   • 1674, [Richard Allestree], “Of Positiveness”, in The Government of the Tongue. […], Oxford, Oxfordshire: At the Theater, →OCLC, page 197:

     Nay, if he be of a proud humour, […] he will not Bate an Ace of abſolute certainty, but however doubtful or improbable the thing is, coming f[r]om him it muſt go for an indiſputable truth.

   • 1955 December, “Notes and News: An Old Midland Railway Bridge Notice”, in Railway Magazine, page 877:

     It is highly improbable that the drafter of the notice ever visualised the form that heavy vehicles of the future would take, but the comprehensive wording still covers modern types.

2. Not likely to happen.

   Due to the loss of power, it is improbable that we will begin on time.

Antonyms

• probable

Derived terms

• improbability
• improbableness
• improbably
• statistically improbable phrase
• superimprobable

Related terms

• probability
• probably

Translations

not likely to be true

• Armenian: անհավանական (hy) (anhavanakan)
• Belarusian: непраўдападо́бны (njeprawdapadóbny)
• Bulgarian: неправдоподо́бен (bg) (nepravdopodóben)
• Catalan: improbable (ca)
• Czech: nepravděpodobný
• Dutch: onwaarschijnlijk (nl)
• Finnish: epätodennäköinen (fi)
• French: invraisemblable (fr)
• Georgian: არასარწმუნო (arasarc̣muno), წარმოუდგენელი (c̣armoudgeneli), არადამაჯერებელი (aradamaǯerebeli), დაუჯერებელი (dauǯerebeli), დამაჯერებლობას მოკლებული (damaǯereblobas moḳlebuli), ნაკლებად შესაძლებელი (naḳlebad šesaʒlebeli), ნაკლებად სავარაუდო (naḳlebad savaraudo)
• German: unwahrscheinlich (de)
• Greek: απίθανος (el) (apíthanos)
• Hungarian: valószínűtlen (hu)
• Japanese: 疑わしい (ja) (utagawashii), 低確率の (teikakuritsu no)
• Polish: nieprawdopododny
• Portuguese: improvável (pt)
• Romanian: improbabil (ro)
• Russian: неправдоподо́бный (ru) (nepravdopodóbnyj)
• Slovak: nepravdepodobný
• Spanish: improbable (es), inverosímil (es)
• Swedish: osannolik (sv)
• Ukrainian: неправдоподі́бний (nepravdopodíbnyj)

not likely to happen

• Armenian: անհավանական (hy) (anhavanakan)
• Belarusian: невераго́дны (be) (njevjerahódny)
• Bulgarian: невероя́тен (bg) (neverojáten)
• Danish: usandsynlig
• Dutch: onwaarschijnlijk (nl)
• Finnish: epätodennäköinen (fi)
• French: improbable (fr)
• Galician: improbable (gl)
• German: unwahrscheinlich (de)
• Greek: απίθανος (el) (apíthanos)
• Hungarian: valószínűtlen (hu)
• Japanese: 疑わしい (ja) (utagawashii), 低確率の (teikakuritsu no)
• Portuguese: improvável (pt)
• Russian: невероя́тный (ru) (neverojátnyj)
• Spanish: improbable (es)
• Swedish: osannolik (sv), föga troligt
• Ukrainian: неймові́рний (nejmovírnyj)

The translations below need to be checked and inserted above into the appropriate translation tables. See instructions at Wiktionary:Entry layout § Translations.

Translations to be checked

• Irish: ^{(please verify)} andóch
• Italian: ^{(please verify)} improbabile (it)

See also

• impossible

Catalan

Adjective

improbable m or f (masculine and feminine plural improbables)

1. improbable, unlikely

   Antonym: probable

Derived terms

• improbablement

Related terms

• improbabilitat

Further reading

• “improbable”, in Diccionari de la llengua catalana [Dictionary of the Catalan Language] (in Catalan), second edition, Institute of Catalan Studies [Catalan: Institut d'Estudis Catalans], April 2007
• “improbable”, in Gran Diccionari de la Llengua Catalana, Grup Enciclopèdia Catalana, 2026
• “improbable” in Diccionari normatiu valencià, Acadèmia Valenciana de la Llengua.
• Alcover, Antoni Maria; Moll, Francesc de Borja (1963), “improbable”, in Diccionari català-valencià-balear (in Catalan)

French

Etymology

From im- +‎ probable.

Pronunciation

• IPA^(key): /ɛ̃.pʁɔ.babl/

• Audio (Canada (Shawinigan)):

  (file)

Adjective

improbable (plural improbables)

1. unlikely, improbable (not likely)

   Synonym: peu probable

Further reading

• “improbable”, in Trésor de la langue française informatisé [Digitized Treasury of the French Language], 2012

Galician

Alternative forms

• improvável (reintegrationist)
• improbábel

Adjective

improbable m or f (plural improbables)

1. improbable (not likely to happen)

   Antonym: probable

Derived terms

• improbabilidade

Further reading

• “improbable”, in Dicionario da Real Academia Galega (in Galician), A Coruña: Royal Galician Academy, 2012–2026

Spanish

Pronunciation

• IPA^(key): /impɾoˈbable/ [ĩm.pɾoˈβ̞a.β̞le]
• Rhymes: -able
• Syllabification: im‧pro‧ba‧ble

Adjective

improbable m or f (masculine and feminine plural improbables)

1. improbable, unlikely

   Antonym: probable

Derived terms

• improbabilidad
• improbablemente

Further reading

• “improbable”, in Diccionario de la lengua española [Dictionary of the Spanish Language] (in Spanish), online version 23.8.1, Royal Spanish Academy [Spanish: Real Academia Española], 15 December 2025