This was my my favourite pasta sauce to eat when I was in Italy last year. When I wasn't gluten-free yet, aka the good old days.
'Arrabiata.' It means 'angry' in Italian, and the reason for the sauce being labelled with this name is because of the spice of the red pepper flakes. At the restaurants that I ate at in Italy, Arrabiata meant a spicy red sauce with chunks of pancetta in it. Back home, it seems to just mean a spicy red sauce, and an Amatricana sauce is the one that has the pancetta chunks. I was happy when I stumbled across this Giada de Laurentiis recipe for Arrabiata sauce from my copy of her Everyday Pasta cookbook, because it combined both the spice of the red pepper flakes and the pancetta like I remembered.