a move in square dancing in which two dancers face each other, then step forward and left until they have right shoulders adjacent, then move to a position where they are back to back, then move to have left shoulders adjacent, then return to facing each other
bib; (by extension) start number (on a sportsman's shirt); pinny (colorful overshirt worn over one's clothes, usually to mark one's team during group activities)
back of furniture, to rest the sitter's back on; dossier; folder; an organizer to keep papers in, to be stored as a single unit in a filing cabinet, see folder; case, notably legal