What Was That

"What Was That" is a song by New Zealand singer-songwriter Lorde. It was released on 24 April 2025 through Universal and Republic Records as the lead single from her fourth studio album, Virgin (2025). Lorde and Jim-E Stack wrote the track, and they produced it with Dan Nigro. "What Was That" is a synth-pop, dance, and electropop song, with a drum instrumentation inspired by the drums on the 2007 song "Reckoner" by English rock band Radiohead. In the lyrics, the narrator reminisces about a previous relationship and its aftermath.

The song received positive reviews from music critics, who praised its lyrics and its production elements, which received comparisons to her earlier works. It was included in Rolling Stone's best songs of 2025, reached number one in New Zealand, and charted inside the top 20 in Australia, the United Kingdom, and the Billboard Global 200 chart. Lorde and Terrence O'Connor directed the music video for "What Was That", which shows Lorde walking alone through various parts of New York City before culminating in a spontaneous dance performance at Washington Square Park, where she was surrounded by fans recording the moment.