Meinir is from the Welsh Meinir — tall slim maiden, graceful young woman from Welsh main (slim/slender). Meinir is one of the Welsh feminine names — central to traditional Welsh cultural heritage. Welsh feminine name reflecting Celtic Indigenous heritage.
Meinir 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 Meinir reduce to 5, The Seeker. This is a traditional interpretive system, not a factual claim about the name.