Irish for ejaculating your "load", which contains semen and sperm, all over a sluts face, and hopefully she will have the common decency to fuck off afterwards.
A common practice in Ireland usually without the slut fucking off as they want more muck.
" jasus would ya look at that whooer!" said a Fat ugly Irish man
" She deserves the muck" said his even fatter girlfriend "BLow the Muck on her face" said the fat ugly Irish man with a grin on his face
" No thats my dinner" said the irish model (Fat woman)
A flirtatious gesture, generally used as a silent way to ask the second party if they "wanna fuck?" Not to be confused with the same gesture meaning "fuck you!"
All it took to get lucky, was "blowing smoke in someones face". And her smile was the only answer he needed.