This is the 13599th most frequent Russian word.
недействительности
"Invalidity" or "nonexistence."
Here, "недействительности" refers to the invalid status or inapplicability of the signature as a reason for the document's invalidation.
Документ был признан недействительным из-за недействительности подписи.
The document was declared invalid due to the invalidity of the signature.
In this sentence, "недействительности" is used to describe the concept or fact of a contract being invalid as the focus of legal debate.
Вопрос недействительности договора стал центральным в судебном процессе.
The issue of the invalidity of the contract became central in the trial.
Here, "недействительности" conveys the concept of invalidity or inapplicability in an abstract or theoretical context regarding assumptions.