"Supersonic" is a triumphant call to self-determination, urging listeners to embrace who they are with lines like "I need to be myself / I can't be no-one else." The lyrics, often described as a kind of "lumpen nonsense poetry" with "half-baked" allusions, were largely inspired by a few days the songwriter experienced in Liverpool. Written in a single day, this debut single from their album Definitely Maybe was quickly recorded and mixed, capturing a raw energy. At its heart, the song champions self-confidence and a carefree spirit, even nodding to influences like the Beatles.