The term Friend refers to the fact that anyone you friend can read protected entries unless you secure them to a friends group. You can actually read public entries from a journal with an rss feed and that would in fact be a subscriber. I guess they could have called it your snoogle page but friend was easier. As to "friend removed" according to the ystem they were an LJ friend until you removed them, and the phrase "friend removed" is present tense so you are removing an entity that LJ calls a friend from your friends page. I guess a phrase like "you have pissed khoath off your friends page" or "you have wiped khoath" would upset people a bit more.