"Waterfall" by StarGate featuring P!nk and Sia is a song about being deeply connected to someone and trusting them completely. The lyrics describe the feeling of being in love and the vulnerability that comes with it. The first verse sung by P!nk talks about feeling scared by how deeply the other person's love affects her. She also mentions feeling the physical impact of their connection, as her skin still burns from the last time they were together. However, despite her fear, she can't resist their connection and is drawn back to it.

The chorus sung by Sia and P!nk repeats the line "I'm in your waterfall" over and over again, emphasizing the feeling of being swept away by someone's love. They both feel like they're immersed in this person's love and can't escape it, but they don't want to. They're content to be lost in it.

The second verse sung by Sia describes how this person is like oxygen to her and helps her stay grounded when everything else feels chaotic. She trusts them completely, even when the "rapids" of life are overwhelming. This feeling is repeated in the bridge, where the word "waterfall" is repeated, representing the overwhelming and unstoppable force of their love.

Overall, "Waterfall" is a song about the intense emotional connection between two people and the trust and vulnerability that comes with that connection. The lyrics convey the feeling of being swept away by love and the comfort of being with someone who makes you feel safe and grounded.