Interstices (Catholicism)
In Roman Catholicism, the interstices is a period of at least three months between the ordination of a man to the diaconate and his ordination to the priesthood. A bishop may shorten the length of this interval if he has an extraordinary reason for doing so. It is generally longer than three months.[1]
It has been applied to many other offices as well. When rules for the progression of a candidate through church offices were first codified in the 4th and 5th centuries, for example, some bishops established a waiting period of four years as acolyte or subdeacon and five years as a deacon.[2]