n. 25B6; noun
the work was done by slaves : historical serf, vassal, thrall; archaic bondsman, bondswoman.
Anna was his willing slave : DRUDGE, servant, man/maid of all work, lackey; informal gofer; Brit. informal skivvy, dogsbody, poodle.
servile.
freeman, master.
25B6; verb slaving away for a pittance : TOIL, labour, grind, sweat, work one's fingers to the bone, work like a Trojan/dog; informal work one's socks off, kill oneself, sweat blood, slog away; Brit. informal graft; Austral./NZ informal bullock; poetic/literary travail; archaic drudge, moil.