What is the origin of the idiom "head honcho" and when to use it?

The exact origin of the term "head honcho" is believed to have originated from the Japanese language during the American occupation of Japan after World War II. It is thought that American soldiers picked up the Japanese word "hancho," which means "squad leader" or "group leader," and brought it back with them to the United States. Over time, the term "hancho" was anglicized to "honcho," and its meaning evolved to refer to someone who is in charge or a boss.