Imbecile was a medical category of people with moderate to severe intellectual disability, as well as a type of criminal. The term arises from the Latin word imbecillus, meaning weak, or weak-minded. It included people with an IQ of 26–50, between "idiot" (IQ of 0–25) and "moron" (IQ of 51–70). The meaning was further refined into mental and moral imbecility. The concepts of "moral insanity", "moral idiocy"," and "moral imbecility", led to the emerging field of eugenic criminology, which held that crime can be reduced by preventing "feeble-minded" people from reproducing.