Clio (Κλειώ) is from the Greek kleos, meaning "glory" or "fame." The Greek muse of history, daughter of Zeus and Mnemosyne. The Clio Awards in advertising are named for her.
Clio is rare but distinctive. Clio Cresswell is the Australian mathematician.
Clio 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 Clio reduce to 3, The Communicator. This is a traditional interpretive system, not a factual claim about the name.