What distinguishes a simile from a metaphor?

The distinguishing factor between a simile and a metaphor lies in their structural use of language. A simile explicitly compares two different things by utilizing the words "like" or "as." For instance, saying "as brave as a lion" clearly shows the comparison between bravery and the lion using the word "as." In contrast, a metaphor makes a direct assertion that one thing is another, such as saying "time is a thief," which equates time directly to a thief without using comparison phrases.

This fundamental difference in syntax and purpose allows similes to clarify a comparison while metaphors evoke broader thematic interpretations or imagery. Therefore, understanding that similes use "like" or "as" and metaphors state equivalence enables deeper appreciation and analysis of literary devices in language.