referring to a branch that is three-cornered or triangular in cross-section

तीन-कोणीय या त्रिकोणीय आकार की शाखा

English Usage: The triquetrous branch of the plant was unique among its peers.

Hindi Usage: पौधे की तीन-कोणीय शाखा अपने समकक्षों में अद्वितीय थी।