1.
leak, leakage
The escape of liquid, gas, light, or information through an unintended opening or breach. Used for both physical leaks (water, gas) and abstract leaks (information, data).
2.
omission, oversight, something left out
Something that was missed or left out from a list, count, or process. Implies an unintentional gap or oversight.
Usage
The noun form of the verb 漏れる (to leak). Very productive as a suffix attached to other nouns to describe specific types of leaks or omissions.