A common phrase used in and around Northern Ireland, especially Belfast. Refers primarily to men, acquaintances to whom you have a passing familiarity, who you would nod to but not really speak at length to and never invite anywhere. It's also used to greet someone you haven't met in a while in a friendly way when you aren't sure of mutual status relationships but feel that you both fall into the same basic group.

Usage:
"how about ye Big Lad?"

Translation:
"How are you old friend?"

It can also just mean "Big Lad", ie a big male person who is fairly young.