Honcho
Etymology
From Japanese hanchō (“squad leader, group leader”), from han (“squad, group”) plus chō (“head, chief”). American servicemen picked it up during the occupation of Japan and the Korean War. Because chō already means “head,” the common phrase “head honcho” is quietly redundant.
noun · /HON-choh/
The person in charge — the one actually running things.
What it names
The leader on the ground, the boss whose say goes, distinct from whoever merely holds a title above them.
Example
Talk to the honcho on the loading dock; nothing ships without her signature.
Related idea
A boss is whoever ranks above you; honcho stresses the person actually in charge, the one running the show.