One Black wing / perched
Step-by-step explanation:
Metaphor is a figure of speech that is used to describe or compare a person or a thing. The poet, Rita Dove paints a poetic picture of painter and activist, Frida. She introduces us to a character, Frida.
The one black wing refers to the Unibrow which the Frida has perched over her eyes. Dove is using a metaphor to describe Frida's infamous Unibrow as something that is viewed as beautiful.