Iolanthe (Ἰολάνθη) comes from the Greek ion (violet) and anthos (flower) — meaning "violet flower." The name was popularised by Gilbert and Sullivan's 1882 comic opera Iolanthe, about a fairy who marries a mortal.
Iolanthe remains rare but distinctive.
Iolanthe is a compound name. Its parts are ánthos — each an attested element with a recorded meaning of its own.
Iolanthe 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 Iolanthe reduce to 3, The Communicator. This is a traditional interpretive system, not a factual claim about the name.