Britannica Dictionary definition of LAD
[count] informal
1
chiefly British : a boy or young man
- a charming young lad
- Life was hard when I was a lad.
- Well, lad, I hope you won’t make the same mistake again!
- He’s a good lad at heart.
— compare lass
2
British : a man with whom you are friendly : fellow, chap
- They can’t treat us like that, can they, lads?!
- He was out drinking with the lads [=(US) the guys, the boys] at the pub.
◊ In British English, a man who is a bit of a lad does things that are considered a bit wild, such as getting drunk and having sexual relations with many women.
- He was a bit of a lad until he settled down.