Cicely is the medieval English form of Cecilia — from the Latin caecus (blind). Cicely Tyson (1924-2021) — American actress whose 70+ year career was a sustained refusal to play roles she considered demeaning to Black women — she once turned down work for 8 consecutive years rather than accept a stereotype.
Cicely 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 Cicely reduce to 3, The Communicator. This is a traditional interpretive system, not a factual claim about the name.