Fangirl is one who obsesses over celebrities, fictional characters, et cetera. These delicate creatures can also be known as ‘Otakus’, but typically an otaku is one who spends all
day inside, alone, and watching
anime. You could very easily say that a very large proportion of tumblr users are, in fact, fangirls.
However, fangirl isn’t just a name; it’s also and action. For example, you could say you ‘fangirled’ over something, meaning you had a moment in which you probably squealed like a
pterodactyl over something/someone.
Fangirls are VERY sensitive about their
OTP’s, so be careful what you say in front of them...