A category of liens that are typically imposed by a court for reasons of fairness. An equitable lien may arise regardless of whether or not the creditor has physical possession of the property involved.
Definition from Nolo’s Plain-English Law Dictionary
A lien on property, imposed by a court to achieve a fair result. For example, if someone has embezzled money from a business, the business might sue an ask the court for an equitable lien on the embezzler's property. (See also: constructive trust)