* Violation: This is the most common noun form, referring to the act of breaking a law, rule, or agreement.
* Violator: This noun refers to the person or thing that commits a violation.
There are other less common noun forms, such as:
* Violatress: This noun, though less common, refers to a female who commits a violation.
* Violating: This form, though technically a gerund, functions as a noun in some contexts, referring to the act of breaking a law, rule, or agreement itself.
The best noun form to use depends on the specific context of your sentence.