Captain
late Middle English (in the general sense ‘chief or leader’): from Old French capitain (superseding earlier chevetaigne ‘chieftain’), from late Latin capitaneus ‘chief’, from Latin caput, capit- ‘head’.
wiktionary
From Middle English capitain, capteyn, from Old French capitaine, from Late Latin capitāneus, from Latin caput(“head”) (English cap). Doublet of chieftain, also from Old French.
etymonline
captain (n.)
late 14c., capitayn, "a leader, chief, one who stands at the head of others," from Old French capitaine "captain, leader," from Late Latin capitaneus "chief," noun use of adjective capitaneus "prominent, chief," from Latin caput (genitive capitis) "head" (from PIE root *kaput- "head").
Military sense of "officer who commands a company" (rank between major and lieutenant) is from 1560s; naval sense of "officer who commands a man-of-war" is from 1550s, extended to "master or commander of a vessel of any kind" by 1704. Sporting sense "leader of the players on a team" is recorded by 1823. The other Germanic words also are from French.
captain (v.)
"act as leader to, command," 1590s, from captain (n.). Related: Captained; captaining.
