The epic simile is a figurative device first popularized by Homer in his epics. It is a comparison that may be as long as a dozen lines. An epic simile is used typically in epic poetry to intensify the heroic stature of the subject and to serve as decoration.
The epic simile is sometimes called the Homeric simile because it is consciously patterned after the ornate similes composed by Homer in his epics. An ordinary simile describes by using ‘as’ or ‘like’ but the Homeric simile enlarges the comparison so that it becomes a little ‘poem – within a – poem’. Poets also sometimes elaborate a simile by using a description or other metaphors to expand the basic comparison. For example, Milton expands the comparison between Satan’s followers and small flying insects, and then he elaborates it by further comparing their sound, wings, activities, abilities, etc., between them. This kind of elaboration of simile is done in epics, and so it is called ‘epic simile.’ Such a device is decorative in intent.