lacuna

/ləˈk(j)uː.nə/noun
University
1

A small opening; a small pit or depression, especially in bone.

2

A space visible between cells, allowing free passage of light.

3

A small blank space; a gap or vacancy; a hiatus.

4

An absent part, especially in a book or other piece of writing, often referring to an ancient manuscript or similar.

5

Any gap, break, hole, or lack in a set of things; something missing.

6

A language gap, which occurs when there is no direct translation in the target language for a lexical term found in the source language.