The terms "idiot" and "lunatic" were acceptable diagnostic terms in England up until 1959. "Imbecile" and "feeble-minded person" were, likewise, listed as official categories in the 1913 Mental Deficiency Act. England has always lagged a bit behind in discarding outdated terms for the disadvantaged. When I was there in 1980, it was still possible to shop for used clothing at the local Spastic Shop. That is, compared to the United States, where it takes, oh, about twenty-five minutes for a diagnostic euphemism to become a conversational faux pas.
Mary Roach (2010). “Six Feet Over: Adventures in the Afterlife”, p.56, Canongate Books