Originally
酋 meant 'aged/finished wine' (the radical
酉 is a wine vessel) and named the imperial wine officer
大酋 in 《
吕氏春秋》. The semantic shift to 'tribal chieftain' came via the idea of 'eldest/most senior.' Modern usage is mostly in
酋长 (chieftain) and pejorative compounds like
匪酋 (bandit chief),
敌酋 (enemy leader).