I think I've maybe caused some confusion - I posted the OED (the full, comprehensive) definition, which it seems to me is fine (it's labelled as derogatory, and makes it clear it's a stereotype ('applied to', 'supposedly') - that's the one that's staying, because the full OED is a record of historical use of language.
The definition that's being removed is in the article above - it's in the Oxford Advanced Learner's Dictionary, which is for those learning English as a second language to a high level, and reads:
A name used especially in jokes to refer to a type of young woman who is not intelligent, dresses badly, talks in a loud and ugly way and is very willing to have sex
Which is much worse - it doesn't make it clear that it's offensive and a stereotype. It is harder with a learners' dictionary as it's supposed to be written very clearly and simply so perhaps words like 'derogatory' or 'stereotype' weren't considered appropriate. I think taking that out is fine - apart from anything else a learners' dictionary is much shorter than the full OED (which is, in its online version which is now the version of record, entirely unlimited in space) and I don't think it's a term that a learner of English would encounter that frequently any more.