In Chinese poetry, an antithetical couplet is a pair of lines of poetry which adhere to certain rules (see below). It is also called a chunlian, duilian and spring couplet.
Outside of poems, they are usually seen on the sides of doors leading to people's homes or as hanging scrolls in an interior, and often during Chinese new year as a type of fai chun (festive decoration), expressing hope towards the new year.