| ̷ ̷ ̷ ̷ ̷ ̷ ̷ ̷| ̷ ̷ ̷ ̷ ̷ ̷ adjective
: being or relating to a motion-picture sound track in which the sounds are represented by an opaque line of varying width that runs parallel to the length of the film
variable-area track
— compare variable-density