What is Yeah Roy?
1.
When someone says,"Yeah Boys" and you misinterperate them.
(Before a rugby match)
"We gunna win?"
"Yeah Boys!"
"Yeah Roy!"
See
2.
An expression one exclaims when extremely uninterested in a conversation half way into a sentence.
Computer Geek: "Yeah i was on the warhammer website and there was-"
You: "YEAH ROYYY!"
See