The term metonymy denotes a literary trope, that is, a specific form of defamiliarized expression, which indirectly refers to what is at issue. Metonymy achieves this by way of exploiting an already existing association between the term (or terms) used metonymically—the metonym—and the term (or terms) implicitly at issue. Metonymy thus differs from metaphor, among other things, in that it does not invoke an underlying analogy or similarity between what is said and what is at issue. In both ancient and modern criticism, metaphor received significantly more attention than metonymy (partly owed to the fact that the poetic effects of metaphor tend to eclipse those of metonymy, partly because of the stronger appeal of the logical dimension at the heart of metaphor). As a result, metonymy—though widely used—is often ill-defined as a critical concept. Today, it features in literary-aesthetic, diachronic-etymological, (post-)structuralist, and cognitive criticism. Ancient literature, both Greek and Latin, is rich in metonymic usages, albeit with varying degrees of poetic intensity; the pattern is one of relatively few intense outcomes, and relatively many less intense ones. Prominent among the general literary-aesthetic effects of metonymy’s semantic shifts are the creation of a poignantly condensed impression of what is at issue; a change in focalization by zooming out onto a higher plane or zooming in on newly foregrounded micro-level aspects; and movement between the concrete-material and the abstract-conceptual dimensions of what is at issue.