What is Da Say Nay?
1.
It is a cantonese word. Literally it means "I'll hit you to death" but comenly used as "I'll hit you very hard!" Usually shows that you're angry at that person or just hitting randomly. Da means hit, say means death and nay means you.
"I'll da say nay!!"
"I'll da say nay!! You broke the vase!!"
See