Lacuna (noun)

1. A gap, missing part or blank space, especially in a manuscript or text.
2. A small depression, hole or void in a bone or tissue.
3. A blank or missing space in one's knowledge or experience.

Origin:

From the latin word 'lacuna' meaning 'a gap, pit or blank space'.

Examples:

1. The manuscript had several lacunae where pages had been torn away.
2. The lacunae in the bone made it fragile and prone to breakage.
3. His education had a few lacunae as he had missed out on some important classes.
4. The historian filled in the lacunae in the manuscript by consulting other sources.
5. The scientist studied the lacunae in the tissue to understand the disease process.