"slender, thin," 1620s, from Latin gracilis "slender, thin, fine; plain, simple, meager" (source of French grêle), of unknown origin. Not etymologically connected to grace but often regarded as if it is. Perhaps a dissimilated form related to Latin cracens "slender;" if so, perhaps cognate with Sanskrit krsah "thin, weak," Avestan keresa- "lean, meager," Lithuanian karštu "to be very old, to age." Related: Gracility.