Kaja is the Estonian word for "echo, reflection" — also the Scandinavian short form of Katarina (Catherine, "pure"). Reform Party leader 2018-2024.
Kaja 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 Kaja reduce to 5, The Seeker. This is a traditional interpretive system, not a factual claim about the name.