Greek short form of Constantine, from Latin 'constans' meaning constant or steadfast.
Costas is the Greek vernacular form of Konstantinos — itself derived from the Latin *constans*, meaning 'constant' or 'steadfast.' The name traces its prestige directly to Constantine the Great, the Roman emperor who in 313 AD issued the Edict of Milan, legalizing Christianity throughout the empire and reshaping the course of Western civilization. Through Byzantine influence, Konstantinos became one of the most honored names in the Eastern Mediterranean, and Costas emerged as its familiar, everyday diminutive — the name you'd call a friend, a grandfather, a neighbor in Thessaloniki or Limassol.
In modern Greek culture, Costas (and its spelling variant Kostas) is ubiquitous and beloved, ranking perennially among the most common male names in Greece and Cyprus. It carries the easy confidence of a name that has never needed to reinvent itself. Outside Greece, Costas has gained visibility through figures such as British broadcaster and journalist Costas Panayi and various athletes in football and swimming.
In the diaspora — from Melbourne to Chicago to London — it serves as a cultural anchor, a name that announces Greek heritage without demanding explanation. Its rhythm is Mediterranean: open vowels, a rolling middle consonant, a name that sounds like sun on water.