Irish slang meaning getting absolutely off your face drunk, usually while Knacker drinking (on the nac)
Friend: Did you pull that beure last night?
Me: No she was too moudly, she started getting sick everywhere!

Friend: Are we heading to a pub tonight?
Underage Friend: No fuck that we'll go on the nac and get mouldy on the lush instead!
by IrishGuru March 20, 2015
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