Flavia comes from the Roman family name Flavius — from the Latin flavus, meaning "golden" or "yellow-haired." The Flavian dynasty of Roman emperors (69-96 CE) included Vespasian, Titus, and Domitian.
Flavia is widely used in Italy, Spain, and Latin America. The Brazilian actress Flavia Alessandra is a contemporary bearer.
Flavia does not currently appear in the US Social Security Administration's top 1,000 girls' names, so we don't publish a US rank or birth count for it. That says nothing about the name's standing elsewhere in the world — only that it sits outside the ranked US data we rely on.
In Pythagorean numerology the letters of Flavia reduce to 6, The Nurturer. This is a traditional interpretive system, not a factual claim about the name.