Ilomilo

Interview about the meaning of the song:

Billie said: "I used to play ilomilo a lot. I loved ilomilo, that was like my favourite game in the world. It's this game where it's these two little creatures – one is named ilo and the other's named milo. It's this sort of anti-gravity world where there's all these little blocks and they start apart from each other. The idea is you just get to each other and when they get to each other they just hug, there's no prize."

Billie then added: "So the whole idea of the game is just losing the person you love and then finding them again."

In other words, the meaning of 'ilomilo' the song is literally the concept of 'ilomilo' the game and it's just two names put together.1

• 1. https://www.popbuzz.com/music/news/billie-eilish-ilomilo-lyrics-meaning/