A euphemism is an innocuous word or expression used in place of one that is deemed offensive or suggests something unpleasant. Some euphemisms are intended to amuse, while others use bland, inoffensive terms for concepts that the user wishes to downplay. Euphemisms may be used to mask profanity or refer to topics some consider taboo such as mental or physical disability, sexual intercourse, bodily excretions, pain, violence, illness, or death in a polite way.

Profanity involves the use of notionally offensive words for a variety of purposes, including to demonstrate disrespect or negativity, to relieve pain, to express a strong emotion, as a grammatical intensifier or emphasis, or to express informality or conversational intimacy. In many formal or polite social situations, it is considered impolite, and in some religious groups it is considered a sin. Profanity includes slurs, but there are many insults that do not use swear words.