Marcelo is the Spanish and Portuguese form of Marcellus, a Roman family name that is a diminutive of Marcus, so it goes back to Mars, the god of war, and is usually read as "young warrior" or "dedicated to Mars". The Brazilian left-back Marcelo, a Champions League winner with Real Madrid, is its best-known modern bearer. Marcelo has risen steadily from number 842 in 2000 to number 399 in 2025, its best rank so far.