honcho

One who is in charge; a manager or leader: “Now that Hollywood honchos have discovered the verdant beachfront villages, the stores have grown in scope and sophistication” (David Field).

To direct or manage: “He . . . is honchoing preparations for the forthcoming . . . economic summit” (Newsweek).

[Japanese hanchō, squad leader : han, squad (from Middle Chinese pa·n, arrangement, class) + chō, chief (from Middle Chinese triaŋ).]

A slang term describing the leader or person in charge of an organization.

Investopedia Says:
The CEO of a company could be referred to as the honcho or "head honcho."

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noun

One who is highest in rank or authority: boss, chief, chieftain, director, head, headman, hierarch, leader, master. Idioms: cock of the walk. See over/under.

The person in charge which is not necessarily the person assigned to be in charge. See HMFIC.

The noun has one meaning:

Meaning #1: a person who exercises control over workers
  Synonyms: foreman, chief, gaffer, boss