What is the literary device called when a whole is referred to by one of its parts?

The literary device in question is synecdoche, which occurs when a part of something is used to represent the whole or vice versa. This technique is often employed to create a more vivid picture in the reader's mind and to emphasize certain attributes of the whole by focusing on its parts.

For example, in the phrase "all hands on deck," "hands" refers not just to the hands but to the sailors themselves. This use of a specific part to stand in for the larger group creates a concise and impactful expression. Synecdoche enriches language by allowing for more engaging and relatable imagery.

Understanding synecdoche is important in analysis of literature and everyday communication, as it allows one to appreciate the nuanced ways in which language can convey meaning and evoke imagery differently from other devices, such as metonymy, which involves substituting a word with a closely associated concept. Thus, synecdoche serves as a fundamental tool in poetry and prose, enhancing the depth and resonance of the text.