Brief nickname for what was first called the Court of Chancery and later, the Chancery Division, a court dedicated to hearing cases which were based on equity (as opposed to its antagonist, the common law), such as real property, mortgages, company law, patents, trusts and estate matters.
The Court of Chancery actually included a separate common law division (called "ordinary") along with the equity branch, (called "extraordinary").
Historically headed by the Chancellor or now known as the Lord Chancellor. As of more recently, the title Lord Chancellor or Chancellor refers to the British Minister of Justice.