A person who handles monies or property on behalf of another in a trust. He usually has the title to the property but in fact acts merely as a steward, all the benefits belonging to persons known as the beneficiaries. Because he has the legal title, he can dispose of the property to an innocent third party without the consent of the true owner; this would be known as a breach of trust. It is therefore essential that a trustee is one whose integrity is undisputed.
Reference: The Penguin Business Dictionary, 3rd edt.