What is "youngun"

Usage examples of "youngun".

That youngun of yours was out wenching with your crew when he was but sixteen, 98 ,v,.

Had many a fight, he did, younguns being as cruel as they are, up until Viscount Eden befriended him in their college days.

I figured out a way to card wool faster, long time back, me and Vernt did, but Vernt died, and I had to do it by myselfthree younguns, you know.