Is there a term to describe words missing in a document?
Solution 1:
There's some disagreement going on here that can be attributed to differing interpretations of the question.
If the text was once there but is now missing or illegible, it is a lacuna.
If a word or phrase was left out unintentionally, it is an omission or elision.
If a word or passage has been intentionally removed, it is a redaction.
Solution 2:
It sounds like you're talking about lacunae.
Solution 3:
Words deliberately left out or blanked for security reasons would be redacted