(; also , ) is a shortened version of , literally, the person for whose use/benefit the feoffment was made, in modern terms a beneficiary. It is a Law French phrase of medieval English invention, which appears in the legal phrases , , or . In contemporary English the phrase is also commonly pronounced "setty-kay" () or "sesty-kay" (). According to Roebuck, is pronounced . and trust are often interchangeable. In some medieval documents it is seen as . In formal legal discourse it is often used to refer to the relative novelty of a trust itself, before that English term became acceptable. Two subcategories of cestui que (beneficiary) The is the person for whose benefit (use) the trust is created. Any such person is, unless restricted by the trust instrument, fully entitled to the equitable interests such as annual rents/produce/interest, as opposed to the legal ones such as any capital gain, of the property forming the trust assets. Two subsets, B and C, can exist: If land is granted to or held by A, for the use of B in trust for his life, with remainder to C when B dies, A is the trustee, B is , and C the trust. Often B and C will be the same person and if so the two law French terms become synonyms. The duration of for life is not essential, it can be for a term of years, shorter time or for another living person's life, as main lawful examples. As those terms are dated and historic, though not entirely obsolete among some of the judiciary and book writers, the terms "beneficiary" – where a subdistinction is made: initial beneficiary and beneficiary in remainder – are current in general trust law. Original purposes Both s are rooted in medieval law, a legal device for avoiding feudal services (most forms of servitude) due to an overlord, by granting the land for the use of another, one who owed none of these to the lord. The law of tended to defer jurisdiction to courts of equity as opposed to the less flexible common law courts. The device was often used by people who might be absent from the kingdom for an extended time (as on a Crusade, or a business venture), who held a tenancy in the land and in return owed feudal incidents (services) to the landlord. The land could be