Nitroglycerin. NTG is short for Nitroglycerin (not the exploding kind, the medical kind people use for angina).
You're a medical or pharmacy student and you found "NTG" written somewhere in your notes and wondered "what the hell does that stand for?". Fair enough, but then you actually checked Urban Dictionary for it? Really?
by DrugsDrugsDrugs April 16, 2014
Nice Tall Glass used as a preface to " shut the fuck up"
used like have a NTG of STFU or Have a nice tall glass of shut the fuck up
by dylan "bamf" November 24, 2006