I. ˈkler-ē-ən, ˈkla-rē- noun
Etymology: Middle English, from Middle French & Medieval Latin; Middle French clairon, from Medieval Latin clarion-, clario, from Latin clarus
Date: 14th century
1. : a medieval trumpet with clear shrill tones
2. : the sound of or as if of a clarion
II. adjective
Date: 1801
: brilliantly clear
her clarion top notes
also : loud and clear
a clarion call to action