@magdalaaugustinn
If you don't live in the USA, Which is the only place I know of that uses the term...
Per Google...
Definition: Chief (n.)
c. 1300, "head, leader, captain; the principal or most important part of anything;" from Old French chief "leader, ruler, head" of something, "capital city" (10c., Modern French chef), from Vulgar Latin *capum, from Latin caput "head," also "leader, chief person; summit; capital city" (from PIE root *kaput- "head"). Meaning "head of a clan" is from 1570s; later extended to American Indian tribes. Commander-in-chief attested from 1660s. [1]