Something metaphoric is figurative or symbolic — in other words, it's a metaphor. Your mom might use the metaphoric phrase "disaster area" when she talks about your bedroom.
Metaphoric speech or writing emphasizes the similarities between two fundamentally different things, by having one stand for, or represent, the other. For example, the famous line in the play "As You Like It" by Shakespeare, "All the world's a stage," is metaphoric — "a stage" is a metaphor for "all the world." You can also use the adjective metaphorical to mean the same thing. The Greek root of both is metaphora, "a transfer" or "a carrying over."