NOUN (4)

1. religious ministers collectively (especially Presbyterian);

2. building where the business of a government department is transacted;

3. a government department under the direction of a minister;

4. the work of a minister of religion;
- Example: "he is studying for the ministry"

The Collaborative International Dictionary of English v.0.48:

Ministry \Min"is*try\, n.; pl. Ministries . [L. ministerium. See
   Minister, n., and cf. Mystery a trade.]
   [1913 Webster]
   1. The act of ministering; ministration; service. "With
      tender ministry." --Thomson.
      [1913 Webster]

   2. Hence: Agency; instrumentality.
      [1913 Webster]

            The ordinary ministry of second causes. --Atterbury.
      [1913 Webster]

            The wicked ministry of arms.          --Dryden.
      [1913 Webster]

   3. The office, duties, or functions of a minister, servant,
      or agent; ecclesiastical, executive, or ambassadorial
      function or profession.
      [1913 Webster]

   4. The body of ministers of state; also, the clergy, as a
      body.
      [1913 Webster]

   5. Administration; rule; term in power; as, the ministry of
      Pitt.
      [1913 Webster]

WordNet (r) 3.0 (2006):

ministry
    n 1: religious ministers collectively (especially Presbyterian)
    2: building where the business of a government department is
       transacted
    3: a government department under the direction of a minister
    4: the work of a minister of religion; "he is studying for the
       ministry"

Moby Thesaurus II by Grady Ward, 1.0:

123 Moby Thesaurus words for "ministry":
   Sacred College, administration, advisory council, agency, agent,
   aid, assistance, attendance, auspices, bailiwick, benefit, bureau,
   bureaucracy, cabinet, camarilla, care, channel, charge, clergy,
   clerical order, clericals, comfort, commissariat, constablery,
   constablewick, constabulary, council, council of state, cure,
   custodianship, custody, department, directorate, divan, ease,
   employ, employment, good offices, governance, government,
   guardianship, guidance, hands, help, hierarchy, higher echelons,
   higher-ups, holy orders, instrument, instrumentality,
   instrumentation, jurisdiction, keeping, kitchen cabinet,
   management, mean, medium, ministration, municipality, office,
   offices, officialdom, organ, oversight, pastorage, pastorate,
   pastorship, patronage, peonage, prelacy, presbytery, priestery,
   priesthood, privy council, protection, protectorship, rabbinate,
   relief, religion, remedy, rescue, ruling class, ruling classes,
   sacred calling, safe hands, secretariat, serfdom, service,
   servitium, servitorship, servitude, shadow cabinet, sheriffalty,
   sheriffwick, shrievalty, slavery, stewardship, succor, support,
   tendance, the Establishment, the administration, the authorities,
   the church, the cloth, the ingroup, the interests,
   the people upstairs, the power elite, the power structure,
   the pulpit, the top, them, therapy, they, top brass, tutelage,
   vehicle, ward, wardenship, wardship, watch and ward, wing