Kind of.Plato in 400BC already proposed breeding out the “weak”, so it’s not like the idea of eugenics is particularly new. The word “moron” was created in the 20th century as a “scientific” word… by one of the main proponents of the modern eugenics movement, which started in the 19th century, with no prior use, so yeah, that one is definitely burned. “Dullard” comes from 10th century English, already with a derogatory meaning, but it seems like English preferred using “lunatic”, “mad” or “insane” in its legal wording. “Idiot” comes from ancient Greek meaning “layman”, “ignorant”, later “illiterate”, and only in the 14th centuries it came to mean “stupid” or “mentally deficient”, and then it went on to differentiate the “mentally deficient” from the “lunatics” (mentally ill). “Imbecile” is more interesting, it seems to stem from the Latin “in-bacillus” or “without little staff”… which has gone through the meanings of “weak”, “cowardly”, “impotent”… and knowing Romans and their insults, is likely to have started as just “dickless”, which is kind of mild for the period. There is however some 17th century legal stuff where women got considered as invalid witnesses “because of imbecility and sexual frailty”, which seems to be about when the word took its modern meaning. Overall, the Eugenics movement seems to have mostly used words that were already established for centuries, just pushed them a few steps farther.