Aila is from the Finnish Aila — variant of Aili / Helga — from Old Norse heilagr (holy, blessed); also Finnish Sami aila (dawn). Aila is one of the Finnish + Sami feminine names.
Aila 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 Aila reduce to 5, The Seeker. This is a traditional interpretive system, not a factual claim about the name.