Wikepedia states

“Much like today’s socially acceptable terms idiot and moron, which are also defined as some sort of mental disability, when the term retard is being used in its pejorative form, it is usually not being directed at people with mental disabilities. Instead, people use the term when teasing their friends or as a general insult.”

Is it only a slur if directed at soneone with mental disabilities? Is it a slur if durected at onself?

Whats lemmies take on this?