Borne on in

It means nothing to me. Where did ou find that sentence?

I'm sorry.
I made a mistake
I mean "borne in on s.o " which is the past participle of "bear in on s.o"

JumanahI made a mistakeI mean "borne in on s.o " which is the past participle of "bear in on s.o"

That change would not improve your sentence.

This is probably what the writer meant:

Suddenly it dawned on him that he was too old to start a new career.

If something is borne in on/upon someone.
They're made to understand it.
"Suddenly, it was borne in on him that he was becoming too old to start a new career."
I found this in a Cambridge Dictionary.
But I really don't understand the meaning of this word.
Can you please clarify the meaning?

JumanahBut I really don't understand the meaning of this word.

I don't understand it either. It does not fit this context.
The Cambridge Dictionary entry says it is formal British English.
I've never heard this expression before, but I read mostly American English material.
Perhaps one of our British speakers can comment.

AlpheccaStarsPerhaps one of our British speakers can comment.

It seems very unnatural to this speaker of BrE, My flabber was gasted when I saw it in the Cambridge dictionary,