1. something that you are a serious fangirl of, or that makes you have a fangirl moment; very squeesome.
2. The act of being a fangirl.
3. a fangirl moment.
exaple 1- NaruGaara is one of my many fangirlisms.
example 2- My fangirlism never ceases.
example 3- Heh, sorry, I was having a bit of a fangirlism..