Horn-mad is a slang term that means being extremely sexually aroused or lustful. Its antonyms would be words that describe lack of sexual desire, such as frigid, impotent, or asexual. These words imply an absence of sexual appetite, attraction or activity. Other antonyms might include chaste, abstinent or celibate, where a person may choose to refrain from sexual activity for religious or personal reasons. Using antonyms for horn-mad may be appropriate when discussing sex education, describing someone's sexual orientation or preference, or in any context where it's necessary to differentiate between sexual behaviours and attitudes.