dossier (n.) Look up dossier at Dictionary.com
1880, from French dossier "bundle of papers," from dos "back" (12c.), supposedly because the bundle bore a label on the back, from Latin dossum, variant of dorsum "back." Or possibly from resemblance of the bulge in a mass of bundled papers to the curve of a back. Old French dossiere meant "back-strap, ridge strap (of a horse's harness)."