What does "supremo" mean?

The most important person in an organization.

What is a synonym for "supremo"?

Common synonyms include: authority, autocrat, boss, expert, head, leader.

Pronounced //suːˈpɹiːməʊ//.

/suːˈpɹiːməʊ/ noun, slang

noun, slang ·Moderate ·College level

Noun

1
The most important person in an organization. informal
"Kitchener was, of course, Secretary of State for War and virtual military supremo."
2
the most important person in an organization wordnet

"STF is the acronym of Supremo Tribunal Federal."

Borrowed from Italian supremo (“supreme”). Doublet of supreme.