Definitions
1.NounA set of two things, particularly."5th Street is one-way west only and 6th Street is one-way east only. Together, they form a couplet in Downtown Los Angeles."
2.NounA pair of lines, typically with rhyming end words.
3.NounEllipsis of antithetical couplet, Chinese couplet, or duilian couplet (“duilian”).
4.NounA pair of one-way streets which carry opposing directions of traffic through gridded urban areas."5th Street is one-way west only and 6th Street is one-way east only. Together, they form a couplet in Downtown Los Angeles."
5.NounA pair of two mutually exclusive choices in a dichotomous key.