Stem

In audio/video/film production a stem is a group of audio information, not unlike a submix. In fact they are often created using subgroups from a mixer in just the same way as a submix. In film and some video production many different stems are put together during the final stages of mixing (mixdown) to form the final soundtrack. Stems may include foley tracks, music tracks, sound effects tracks, dialog, location sound, etc. Each of these stems is a submix of dozens of individual components each carefully and often individually prepared to enhance the overall experience of the film. Nowadays individual stems are often prepared in full 5.1 or 7.1 surround, which means that “a stem” may actually be comprised of as many as eight separate channels/tracks of information.