Definition of Master in Chancery in US English:

Master in Chancery

noun

historical
  • A senior assistant of the judge or chancellor in a court of chancery; especially (in English law) each of the twelve assistants of the Lord Chancellor, the chief of whom was Master of the Rolls (the office of Master in Chancery was abolished in English law in 1852); formerly also "†Master of (the) Chancery".

Origin

Late Middle English; earliest use found in Rolls of Parliament.