noun
1. : the relation that is declared by a court to exist between parties to a transaction when the court desires to hold the offending party responsible to prevent unjust enrichment as though he were in fact a trustee for the other
2. : the relation existing when one person justifiably reposes confidence, faith, and reliance in another whose aid, advice, or protection is sought in some matter : the relation existing when good conscience requires one to act at all times for the sole benefit and interests of another with loyalty to those interests : the relation by law existing between certain classes of persons (as confidential advisor and the one advised; executors or administrators and legatees or heirs; conservators and wards, trustees, or beneficiaries; partners, joint adventurers, corporate directors or officers and stockholders; majority and minority stockholders; factors, agents, or brokers and principals; attorneys and clients; promoters and stock subscribers; mutual savings banks or investment corporations and their depositors or investors; receivers, trustees in bankruptcy, or assignees in insolvency and creditors)