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.
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.
go on about someone/something
verb
See go on and on about someone/something
go on (and on) about someone/something
in. to rave about someone or something endlessly. Why do you have to go on about your sister so?