What is Constructive Trust?

Legal Definition
A constructive trust is an equitable remedy resembling a trust (implied trust) imposed by a court to benefit a party that has been wrongfully deprived of its rights due to either a person obtaining or holding a legal property right which they should not possess due to unjust enrichment or interference.
-- Wikipedia
Legal Definition
A constructive trust is not an actual trust by the traditional definition. It is a legal fiction that is used as a remedy for unjust enrichment. Hence, there is no trustee, but the constructive trust orders the person who would otherwise be unjustly enriched to transfer the property to the intended party.
Legal Definition
A trust made based on the law preventing injustice. It stops one party from getting an unfair advantage by lieing.
Legal Definition
A (rust raised by construction of law, or arising by operation of law, as distinguished from an express trust. Wherever the circumstances of a transaction are such that the person who takes the legal estate in property cannot also enjoy the beneficial interest without necessarily violating some established principle of equity, the court will immediately raise a constructive trust, and fasten it upon the conscience of the legal owner, so as to convert him into a trustee for the parties who in equity are entitled to the beneficial enjoyment. Hill, Trustees, 116; 1 Spence, Eq. Jur. 511. Nester v. Gross, 66 Minn 371, 69 N. W. 39; Jewelry Co. v. Volfer, 106 Ala. 205, 17 South. 525, 28 In RA. 707, 54 Am. St. Rep. 31.
-- Black's Law Dictionary
Legal Definition
Exists when property is purchased in the name of one, but the consideration is paid by another and such property will be held by the former in trust for the latter. See 97 Cal. 575, 33 Am. St. Rep. 209, 21 L. R. A. 33, 32 Pac. 579.
-- Ballentine's Law Dictionary