Words can have certain meanings, and they can also have positive or negative slants. Dysphemism describes situations where a word with a negative connotation is used instead of other words that could fit easily into the sentence and that give a more negative slant on the meaning of the entire sentence. This substitution of words reflects the attitude of the speaker and shows that he or she feels negatively about the subject.
A euphemism is a term that gives a positive slant to the thing being referred to. When a man calls a girl "thrifty," for example, he means that she does not spend money freely, but he is also saying that she is good with money. This is a positive slant on the description of the girl as he is giving her kudos for her ability to control her money.
Dysphemism is the opposite of euphemism. Instead of the man portraying the girl in a positive manner, a dysphemism portrays her in a negative way. Instead of using "thrifty," he would describes her as "stingy," "mean," or "tight." This tells his audience that he sees her control over money as a negative thing.
People choose to use a dysphemism precisely because the connotation of the word is negative. This can be because the speaker truly thinks the situation is negative or because the speaker is within a comfortable, casual social grouping. A dysphemism also tends to be more forceful in making a point than neutral or euphemistic words as they express a severely negative slant and emotional viewpoint on a topic. When a woman who escapes a bombing attack during a civil war, for example, refers to the attackers as "terrorists," she is telling her audience that she feels strongly negative about the bombers compared to someone who calls the attackers "freedom fighters" or simply "rebels."
In polite society, euphemisms are more appropriate in conversation. Neutral terms, such as a man describing a girl as "careful with her money," are also acceptable, although when a formal gathering talks about topics that are taboo in some way, such as promiscuity, then the euphemism of a term such as "Don Juan" is more acceptable. In some cases, terms that previously were acceptable as euphemisms in polite society, such as "colored" to describe a person with African ancestry, become dysphemisms as time goes by.