Word.ws English Dictionary

deffo

UK/ˈdɛfəʊ/

deffo adjective: definite.

Adjective

deffo (comparative more deffo, superlative most deffo)

  1. (Australia, Canada, Ireland, UK, colloquial, usually) Definite.
    • I know for certain they′re not speaking to each other, that′s for deffo, not that I′ve even seen them in the same room over the last week to confirm their silence.2003, Grace Dent, LBD: it′s a girl thing, page 45
    • ‘An infection. Nothing serious. They′ll have some colour in them soon, for deffo.’2009, Joe Stretch, Wildlife, unnumbered page

Adverb

deffo (comparative more deffo, superlative most deffo)

  1. (Australia, Canada, Ireland, UK, colloquial) Definitely.
    • He told me that he's deffo going to be there tonight.
    • And I deffo don′t believe in me, cos I′m a proper knobhead, aren′t I, and always have been.2009, Nick Leather, Billy Wonderful, page 12

Examples of deffo in a sentence

  • “Couldn′t say for deffo, probably at least fifteen years old, but I know they don′t make them like these any more for exactly the reason you′ve just seen.2009, Stephen Leonard Lancashire, Immaculate Deception, page 271:
  • Needles wilted under the force of Pegg′s demand, his eyes widened and he seemed to shrink in size, and I can′t say for deffo but I think he probably wet himself.2010, Simon Pegg, Nerd Do Well, page 25:

Forms of deffo

Adjective
comparativemore deffo
superlativemost deffo
Adverb
comparativemore deffo
superlativemost deffo

Origin of deffo

From definitely or definite + -o (diminutive suffix).

Words formed from deffo

Questions about deffo

What does deffo mean?
Deffo means definite.
How do you use deffo in a sentence?
“Couldn′t say for deffo, probably at least fifteen years old, but I know they don′t make them like these any more for exactly the reason you′ve just seen.
What part of speech is deffo?
Deffo can be an adjective or an adverb.
How do you pronounce deffo?
Deffo is pronounced /ˈdɛfəʊ/ (UK).

Words near deffo in the dictionary

  1. defeudalizing
  2. deff
  3. deffer
  4. deffered
  5. deffest
  6. deffo
  7. Defford
  8. deffos
  9. DeFi
  10. defiable
  11. defial

Source and license

Adapted from Wiktionary: deffo (page history and authors). Text available under the Creative Commons Attribution-ShareAlike 4.0 license. Word.ws reformatted the entry and added links. Wiktionary data of 2026-09-02.

Last updated:

Pronunciation audio from Wikimedia Commons, each file under its own free license: EN-AU ck1 deffo.ogg.

Cite this entry: “deffo.” Word.ws, https://word.ws/deffo. Based on Wiktionary, CC BY-SA 4.0.