top of the morning (to you)
A generic greeting used in the morning time. (A dated phrase that is nowadays considered to be stereotypical or stock Irish, rather than one that is used ingenuously.) Top of the morning, Bill! That was quite a party last night, wasn't it? A: "Well, top o' the morning to you, my friend!" B: "I wish you would stop saying that to me, just because my dad is Irish."