Trusteeship (noun)

1. The position or duty of a trustee.
2. The state of being held or managed in trust.
3. The administration of a trust by a trustee or trustees.
4. The control or administration of a territory by a foreign country or organization as a trust territory.

Origin:

From trustee + -ship. first attested in the early 17th century.

Examples:

1. The company appointed a new trusteeship to manage the company's assets.
2. He was appointed as the trusteeship of the school.
3. The trusteeship will hold the property until the beneficiary reaches the age of majority.
4. The trusteeship of the territory was transferred to the UN.
5. He took over the trusteeship of the trust from his father.