Changing acceptability
Careful judgements have to be made about the acceptability of certain terms. For example, words such as "faggot", "poof" or "queer" are sometimes used by members of the gay community to describe each other; but the same terms may be deemed offensive when used by a heterosexual, particularly if the terminology is used aggressively or in a clearly pejorative manner.
Likewise, the term "nigger" is occasionally used in the black community and terms such as "cripple" are sometimes used humorously or sarcastically by people with disabilities. But this usage may still cause distress within these communities and is also much more likely to cause offence when employed by someone who is not a member of the requisite community.