Akademik

interstice
noun
a) A small opening or space between objects, especially adjacent objects or objects set closely together, as between cords in a rope or components of a multiconductor electrical cable or between atoms in a crystal.
b) An interval of time required by the Roman Catholic Church between the attainment of different degrees of an order.
Syn: gap, chink, slit, crevice, cranny, crack, fissure

Wikipedia foundation.