Meaning

noun a group of things of the same kind that belong together and are so used

noun (mathematics) an abstract collection of numbers or symbols

noun several exercises intended to be done in series

originFrom Middle English set, sete, sette (“that which is set, the act of setting, seat”), from Old English set (“setting, seat, a place where people remain, habitation, camp, entrenchment, a place where animals are kept, stall, fold”) and Old English seten (“a set, shoot, slip, branch; a nursery, plantation; that which is planted or set; a cultivated place; planting, cultivation; a setting, putting;…

Etymology from Wiktionary, CC BY-SA 3.0