An elegy is a sad or thoughtful poem that is used to mourn the loss of someone who has died. Greek lyric poets often used this type of poem. It's written in elegiac couplets, which is a poetic form of verse consisting of a hexameter verse followed by a pentameter verse.
The word "elegy" came from the Greek word "elegus," which was a lamentation or song that included a flute accompaniment. Elegies can also be written about love and war.
Some of the most famous elegies include Thomas Gray's "Elegy Written in a Country Churchyard" and Walt Whitman's "When Lilacs Last in the Dooryard Bloom'd."