Arete (Ἀρετή) is the Greek word for "excellence" or "virtue" — the highest aspiration of Greek ethics. Arete of Cyrene (4th c. BCE) was the philosopher who succeeded her father Aristippus as head of the Cyrenaic school — the second-oldest known female philosopher after Aspasia.
Arete 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 Arete reduce to 4, The Builder. This is a traditional interpretive system, not a factual claim about the name.