Figurative language, in its broadest sense, is language that uses figures of speech. It is non-literal, and often uses metaphors to make its points.
“White Angel” by Michael Cunningham uses figurative language extensively. A look at the first few lines of the story will reveal several examples. Start with the first lines: “We lived then in Cleveland, in the middle of everything. It was the sixties--our radios sang out love all day long.” That’s vivid description, and not literally true. Cleveland’s not literally in the middle of everything (though it might seem that way to an American or Midwesterner), and the radio doesn’t literally sing (though it plays songs, and there were many love songs in the sixties).
However, I prefer the description of the stillborn children in the family found a few lines later: “Between us were several brothers and sisters, weak flames quenched in our mother’s womb.” His siblings were not literally flames, but their lives flickered and went out as if they were.