Hyperbole

Hyperbole, from the Ancient Greek huperbolḗ by way of Latin (from hupér, "above, beyond," and bállō, "throw"), is "the use of exaggeration as a rhetorical device or figure of speech." In poetry and oratory it "emphasizes, evokes strong feelings, and creates strong impressions," and it is "usually not meant to be taken literally": "the bag weighed a ton" simply means the bag was extremely heavy. The article's modern note is that "literally" itself "has become one of the primary ways to exaggerate and hyperbolize a statement."

In fiction hyperbole is a voice tool more than a truth problem: narrators and characters who overstate consistently read as personalities, and the figure sits in the same family as metaphor and simile. It is also among the cheapest ornaments to overuse; hyperbole in every sentence is one face of purple prose.