I had never heard about this word, but it seems to be somehow popular in slang to refer a leader of a small amount of people.
However note it comes from Japanese, not from Spanish, and it is used in slang English. So, in principle, it does not have anything to do with Spanish.
From Urban Dictionary:
honcho
A person in charge of some group or of some function, usually a male
person. A Japanese word, often mistakenly thought to be of Spanish
origin. In Japanese it's a term for a small-time yakuza gangster in
charge of just a few underlings, but the underworld flavor has mostly
been lost as the word has been adopted into English.
He quickly got promoted to be the head marketing honcho in that dot.com startup.