noun
Refers to a person who leads or commands a group, organization, or military unit. Slightly formal; often used in contexts emphasizing authority and the ability to unify people.
彼はチームの統率者として、全員をまとめた。
As the team leader, he brought everyone together.
その将軍は優れた統率者だった。
That general was an excellent commander.
Specifically a military or organizational commander who gives orders. 統率者 has a broader sense of leading and unifying, not limited to giving commands.
Compound of 統率 (tōsotsu, 'command; leadership') + 者 (sha, 'person'). The exact historical derivation is uncertain, but the word follows a common pattern for forming agent nouns.