be/go/keep on about something

be on about (something)

To speak about something tediously and at great length. Primarily heard in UK. He just kept rambling about literary metaphors and imagery. I didn't know what he was on about! She's always on about some new show she has started watching.
See also: on

go on (and on) about (something)

To continue or speak for a tedious or exasperating length of time. My date kept going on and on about his charity work, never even asking what I do for a living.
See also: go, on

keep (going) on about (something)

To speak about something tediously and at great length. Primarily heard in UK. He just kept going on about literary metaphors and imagery. I didn't know what he was talking about! She always keeps on about some new show she has started watching.
See also: keep, on
Farlex Dictionary of Idioms.

keep (going) on about someone or something

to continue to talk excessively about someone or something. I wish you would not keep going on about Tom and Jill. Don't keep on about my haircut. It's perfect!
See also: keep, on
McGraw-Hill Dictionary of American Idioms and Phrasal Verbs.

be on about

talk about tediously and at length. British informal
See also: on
Farlex Partner Idioms Dictionary

be ˈon about something

(informal) talk about something; mean something: I didn’t know what he was on about. It didn’t make sense.
See also: on, something

be/go/keep ˈon about something

(informal, disapproving) keep talking about the same thing so that people become bored or annoyed: What’s she on about now? Don’t keep on about your terrible journey. It’s so boring.
See also: go, keep, on, something
Farlex Partner Idioms Dictionary
See also:
  • be on about
  • be on about (something)
  • be on about something
  • keep (going) on about (something)
  • ramble on
  • rattle on
  • rattle away
  • at great length
  • explain
  • length