What is "heroic couplet"

n. a couplet consisting of two rhymed lines of iambic pentamenter and written in an elevated style

A heroic couplet is a traditional form for English poetry, commonly used in epic and narrative poetry, and consisting of a rhyming pair of lines in iambic pentameter. Use of the heroic couplet was pioneered by Geoffrey Chaucer in the Legend of Good Women and the Canterbury Tales, and was perfected by John Dryden in the Restoration Age.