* Irony: This is the broadest term and encompasses various situations where there's a contrast between what's said and what's meant. It can be verbal irony, where someone says something but means the opposite, or situational irony, where events turn out the opposite of what's expected.
* Sarcasm: This is a specific type of verbal irony used to express mockery or disapproval. It's often characterized by biting humor and a tone of voice that suggests the opposite of what's being said.
* Satire: This is a broader form of irony used to criticize or ridicule societal issues, institutions, or individuals. It often uses humor, exaggeration, and other literary techniques to expose flaws and provoke change.
* Oxymoron: This is a figure of speech that combines contradictory terms, creating a surprising effect. While not technically using a word to mean its opposite, it does create a sense of paradox and unexpected meaning. For example, "deafening silence."
The best term to use depends on the specific context and the intention behind the use of the word or phrase.