agnomen

Sometimes there was also a fourth name, called the agnomen, added from some illustrious action, or remarkable event.

It was this slight connection with ‘the trade’ which gained for Cromwell the agnomen of ‘the brewer.’

To counteract the confusion that would inevitably arise, an agnomen or "tee-name" is usually appended.

I was a little anxious to know whether her ladyship would honour me with an agnomen.