What do you call it when something is described as less than it is for effect?

The term used when something is described as less than it is for effect is known as understatement. This rhetorical device involves intentionally minimizing a situation or its significance to create a contrast or emphasize the actual reality of the situation. Understatement can add humor, irony, or subtlety to writing or speech, allowing the audience to appreciate the true magnitude of a circumstance through implication rather than direct statement.

For instance, if someone describes a catastrophic event as "kind of unfortunate," they are using understatement to highlight the severity of the event while presenting it in a softer, more understated manner. This technique can engage the audience by forcing them to recognize the weight of the situation without the speaker having to overtly state it.

Other literary devices mentioned, such as hyperbole, alliteration, and antonym, serve different purposes. Hyperbole is an exaggeration used for emphasis or effect, while alliteration focuses on the repetition of initial consonant sounds in a series of words. An antonym refers to a word with a meaning opposite to another word, which does not apply in this context where a comparative discussion of magnitude is in focus. Thus, understatement aptly captures the essence of describing something as less than it is for effect.