Original: Cobain came up with the song's title when his friend Kathleen Hanna, at the time the lead singer of the Riot Grrrl punk band Bikini Kill, spray painted "Kurt Smells Like Teen Spirit" on his wall.
Simplified: The title "Smells Like Teen Spirit" came from when Cobain's friend Kathleen Hanna spray painted "Kurt Smells Like Teen Spirit" on his wall.