The flipside is the less-used side of a two-sided object. The term appears to derive from terminology used to describe the two sides of a phonograph disc, particularly the 45 rpm variety. Before the advent of digital technology, single songs were impressed onto vinyl records. The best-promoted single, the one expected to get the most airplay on radio stations and hence to become the most popular, was defined as the 'A' side. A second, less popular song was included as the 'B' side. In some cases, however, the 'B' side song became the popular one; more rarely, both songs were popular, as was the case with many Beatles records.

The term 'flipside' is also used in popular American idiom to mean 'later', as in the term "Catch you on the flipside," which clearly refers back to the phonographic meaning.

'Flipside' is also a Burning Man-style festival, smaller and more localized.

'flipside' was a punk rock fanzine that lasted from 1977 - 2001 from Los Angeles .It also had a punk rock record label, flipside records. It released the first Beck recordings; a split 7 with the band Bean, and his first album, Stereopathetic Soulmanure. It also released an album by the band At The Drive In.