1. deffo - Adjective
2. deffo - Adverb
deffo (comparative more deffo, superlative most deffo)
(colloquial, Australia, UK, Ireland, Canada, usually with "for") Definite.
deffo (comparative more deffo, superlative most deffo)
(colloquial, Australia, UK, Ireland, Canada) Definitely.
He told me that he's deffo going to be there tonight.