What does the term 'metaphor' refer to in literature?

The term 'metaphor' refers to a direct comparison between two unlike things without using "like" or "as." This literary device allows writers to create more vivid and imaginative descriptions, conveying deeper meanings and connections between the concepts they are discussing. For instance, saying "Time is a thief" suggests that time stealthily takes away moments without explicitly saying it is like a thief, which enhances the imagery and impact of the statement.

In contrast, a comparison that explicitly uses "like" or "as" is categorized as a simile, which is less direct. The other options relate to different aspects of literature that do not define metaphor properly. A type of poem refers to a specific genre, while a character's backstory is a narrative element that provides context about a character's history. Thus, the definition of a metaphor as a direct comparison without using "like" or "as" is clearly accurate and fundamental to understanding its role in literature.