Mafalda is the Portuguese-Italian form of Matilda — from Old German maht (might) and hild (battle). Mafalda of Portugal (1195-1256) was the queen of Castile and later beatified — daughter of King Sancho I of Portugal.
Mafalda is also the iconic comic-strip character by Argentinian Quino (1964-1973).
Mafalda 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 Mafalda reduce to 2, The Peacemaker. This is a traditional interpretive system, not a factual claim about the name.