go off on one

English

Verb

go off on one (third-person singular simple present goes off on one, present participle going off on one, simple past went off on one, past participle gone off on one)

1. (British, colloquial) To launch into an animated diatribe, or passionate description or explanation of something.

   I barely mentioned the band's name before he went off on one about how commercial the top forty is these days.

   • 2021, Andreina Cordani, The Girl Who...:

     As far as I was concerned, we had a deal – she never went off on one about 'that's not a skirt it's a belt,' and I never went out dressed like a stripper.

Related terms

• go off on a tangent