interstice

A space, especially a small or narrow one, between things or parts.

An intervening space; an opening; especially, a small or narrow space between apposed surfaces or things; a gap, chink, slit, crevice, or cranny.

In canon law, the interval of time required for promotion from a lower to a higher degree of orders.

That which intervenes between one thing and another; especially, a space between things closely set, or between the parts which compose a body; a narrow chink; a crack; a crevice; a hole; an interval.

An interval of time; specifically (R. C. Ch.), in the plural, the intervals which the canon law requires between the reception of the various degrees of orders.