A Lesson on 'Unmoral', 'Immoral', 'Nonmoral', and 'Amoral' —- All them have prefixes meaning "not." So which to use when?
1. Unmoral refers to those having no moral perception. It is best used for animals or inanimate objects incapable of considering moral concerns, but can also be used for humans lacking the same.
"Many young people today are unmoral rather than immoral," Judge Leahy explained 72 years ago. "Because they have been reared in homes with such low standards of marriage and family behavior, they actually don’t know right from wrong."
— Gary Brown, The Repository(Canton, Ohio), 9 July 2018
2. Immoral refers to a conscientious rejection of typical moral standards and has a connotation of evil or wrongdoing.
The negative prefix im- connects with moralsoon after the formation of unmoral. Immoral describes a person or behavior that conscientiously goes against accepted morals—that is, the proper ideas and beliefs about how to behave in a way that is considered right and good by the majority of people.
Immoralconnotes the intent of evilness or wrongdoing, and it is a true antonym of moral.
3. Nonmoral describes actions that are not usually subject to moral concerns, such as which shirt to wear.
Decades, centuries, go by before moral is linked to another negative prefix, non- (in the 19th century). Nonmoral has the specific meaning of "not falling into or existing in the sphere of morals or ethics." Thus, a nonmoral act or action is not subject to moral judgment because morality is not taken into consideration. Spilling milk is a nonmoral act, and although you might be judged by the clothes you wear, your decision to wear them is nonmoral.
“So in another part of the survey, we asked about basic cognitive faculties, like executing voluntary movements and object recognition…; about nonmoral personality change, like extroversion, sense of humor, creativity and intelligence…. “
— Nina Strohminger and Shaun Nichols, The New York Times, 23 Aug. 2015
4. Finally, amoral implies an awareness of moral standards, but a lack of concern for them while acting.
Amoral appears in the late 1800s. The prefix a-means "not" or "without," as in atypical or asymptomatic. The dictionary definition of amoral is "having or showing no concern about whether behavior is morally right or wrong"—compendiously, "without morals." For example, an infant, unlearned in what is right and wrong, is amoral; someone who lacks the mental ability to understand right or wrong due to illness might be described as amoral. These are illustrative examples, however; amoral can be used to describe any person, or his or her actions, who is aware of what is right and wrong but does wrong anyway and responds indifferently about it.
“… if you hooked him up to a lie detector test, he could say one thing in the morning, one thing at noon, and one thing in the evening, all contradictory and he would pass the lie detector each time. Whatever lie he is telling at that minute, he believes it. But the man is utterly amoral. Morality does not exist for him. “
— Ted Cruz, quoted in The Examiner (Washington, DC), 3 May 2016