Marielle is from the French Marielle — diminutive of Marie (from the Hebrew Miryam). Marielle Franco (1979-2018) was a Brazilian human rights activist, politician, and Rio de Janeiro city councilwoman — widely considered one of the figures of 21st-century Brazilian civil rights + LGBTQ+ activism. Born in the Maré favela of Rio de Janeiro, Marielle was a Black queer single-mother sociologist + favela rights advocate. Fifth-most-voted councilwoman in Rio's 2016 election. martyr of modern Brazilian human rights movement.
Marielle 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 Marielle reduce to 3, The Communicator. This is a traditional interpretive system, not a factual claim about the name.