The Collaborative International Dictionary of English v.0.48:

Stewardship \Stew"ard*ship\, n.
   The office of a steward. --Shak.
   [1913 Webster]

WordNet (r) 3.0 (2006):

stewardship
    n 1: the position of steward

Moby Thesaurus II by Grady Ward, 1.0:

75 Moby Thesaurus words for "stewardship":
   administration, auspices, captainship, care, chairmanship, charge,
   convenership, cure, custodianship, custody, dictatorship,
   directorate, directorship, eagle eye, foremanship, generalship,
   governance, government, governorship, guard, guardedness,
   guardianship, guidance, handling, hands, headship, intendancy,
   invigilation, jurisdiction, keeping, leadership, lookout,
   management, managership, mastership, means of dealing, ministry,
   monitoring, observance, overseership, oversight, pastorage,
   pastorate, pastorship, patronage, peeled eye, presidency,
   proctoring, proctorship, protectorship, prudence, qui vive,
   safe hands, sharp eye, sovereignty, superintendence,
   superintendency, supervisorship, surveillance, treatment, tutelage,
   usage, vigil, vigilance, ward, wardenship, wardship, wariness,
   watch, watch and ward, watchful eye, watchfulness, watching,
   weather eye, wing