The name Joelle is a girl's name meaning "Jehovah is his God". Joelle is ranked #671 on our popularity charts and is often added to lists like Sci-Fi Baby Names and discussed in our forums with posts like "makeover girls!".
From the experts:
Joel is one of those boys’ names that's never been super-popular yet has never been UNpopular either -- it's been in the Top 400 in the US since we started keeping statistics in 1880. So it's inevitable that its female form Joelle would gain visibility too, and indeed Joelle was used most widely during Joel's reign in the Top 100, from the late 1960s through the early 1990s. Joelle reentered the US Top 1000 in 2016 after a decade long absence. It had been just outside the Top 1000 almost all of those years, so its reentry is no surprise. It's also popular in the Netherlands. Pronounciation is distinctively two syllables, as if it were two names: Jo Elle. Joel, on the other hand, rhymes with bowl and roll.