[HPforGrownups] Why did Snape call Lily a 'Mudblood'?

[Peggy Kern]

No: HPFGUIDX 177555

Jen:  Wow, it's a slow list day! I've got a question for a slow day: why
*did* Snape call Lily a Mudblood?

Peggy now:  I think Snape was humiliated and angry at the way he was being 
treated, and just spouted off what came to his mouth at the moment, kind of 
like a person who hits their thumb with a hammer.  He was around people who 
used those terms freely, though in everyday life he would probably never 
dream of using such a term for his friend Lily.  But in the humiliation of 
the moment, it just burst forth from him, and was something he regretted for 
the rest of his life.  I imagine if he hung out with a different group of 
people, who didn't use those kinds of words, he might have used some other 
word to express his frustration.  But his choice of words, in Lily's mind, 
suggested that he bought into the blood thing, and no amount of apologizing 
on his part could convince her otherwise.

Peggy