I know the term “retarded” is banned under the TOS, but the other day I was writing a comment about a person I briefly encountered as a child who was what we would have called “retarded” a few decades ago (he was a teenager who could barely speak and was not able to attend school with his younger sister, who was my classmate). I think I ultimately described him as having severe mental deficiencies, but that’s a rather awkward turn of phrase.
Do the mods have any advice on what term would be acceptable to describe someone with severe, inherited mental deficiencies?