Last name Sinfrônio (Sinfrônio 
) , all around the world, is an extremely rare cognomen. The cognomen Sinfrônio is habitual in Latin America and the Caribbean, particularly Brazil, where it is an extremely rare surname. Likewise, Sinfrônio is the forename as well as the last name.
| VARIANT | COUNTRY |
|---|---|
| Sinfrônio | Brazil |
| sinfrônio de souza campos person identified in the Museu da Pessoa collection, BR (b. 1905) |
|