"Notion" is a song recorded by American rock band Kings of Leon. The song was released as the fourth single (fifth in Australia) from their 2008 album, Only by the Night, on June 29, 2009. The song reached number one on the Billboard Alternative Songs chart for one week in of September 2009.
On the Canadian Hot 100, the song peaked at number 52.
Despite heavy radio play on BBC Radio 1, the song missed the UK Singles Chart top 100 and peaked at number 107, the first time the band had missed the UK top 100 for a single.
The song has peaked at number 46 on the Australian ARIA Charts and has also become a radio hit there peaking at number six on the Australian Airplay charts.
A music video was shot as a promotional effort for the single and was released on June 1, 2009. The director was Phil Griffin. It captures the band performing in a dimly-lit, debris-filled room with imploding fiery brick walls adjacent to an alleyway bordered by another brick barrier that is used by the lead singer in a manner suggestive of the Wailing Wall in Jerusalem.