Irish slang is quite funny. And unique I think. For years now, anything that is really great is "deadly", usually preceded by "bleedin'", however the emphasis must be on the BLEED with the rest sort of trailing off, then again on the DEAD with the LY a little lighter, so: "That show was BLEEDin' DEADly, wasn't it?"
Scarlet is when you're embarrassed, can also be used (like most Irish phrases) in conjunction with the aforementioned bleedin', so, "Jaysus (Jesus)! I'm BLEEDin' SCARlet, I am!" Footnote: as you can see, the emphasis is again on the first syllable, as in "scar", however unlike "deadly", the "t" is generally silent, so it's more "SCARle'" than "SCARLET" --- sort of sounds like "scarla".
"Mot" is girlfriend. "You takin' yer mot out tonight?" Again, drop the t, this is because "mot" is actually from an Irish phrase, "Maith an cailinn" (maw on coleen) meaning, good girl.
"Lanterin' ****!" Sort of self-explanatory, exclamation of surprise or dismay, drop the g on "lantering" --- origin unknown.
"Holy sweet divine!" Another one: what do you expect in a country of Catholics?
These are, in fairness, the slang I, as a nearly-fifty-year-old know. I'm sure there's "street words/phrases" out there now that I wouldn't have a clue about. Or as we say here, wouldn't have a breeze about...