means A person entrusted to manage, care for, or look after something on behalf of others — whether a household, a flight, an estate, or the planet itself.

from From Old English stigweard, literally "sty-ward" — the keeper (weard, "guard") of the sty or hall (stig, possibly "house" or "pen"). It began humbly, the one who watched the animals and the great house, then climbed the social ladder over the centuries until stewards ran estates, ships, and royal households — never owning, always tending.