I've always found the term mental asylum inappropriate for mental deficiency colonies as it leads to the misconception that they were for the mentally ill. I think you'll also find that mental deficiencies were principally set up for the "reception, segregation and training" of 'mental defectives' and were firmly based within the eugenics movement of the early 20th century as opposed to the "maintenance and care" role that their eventually aging populations eventually required.
Theres nothing to stop anyone calling such places 'asylums' of course, its just that the vast majority of them never actually were! I guess people prefer the term for the evocative and sometimes sinister connotations that they suggest.
I know i'm splitting hairs but personally I feel that we're muddying the information pool more than a little but just calling a place whatever we fancy but then i guess my motives are different to others?
