This is the 13697th most frequent Russian word.
непозволительное
"Unallowable" or "unacceptable."
Here, 'непозволительное' is used as an adjective to describe behavior as something not allowed or inappropriate based on social or situational rules.
Её поведение на собрании было непозволительное.
Her behavior at the meeting was unacceptable.
'Непозволительное' describes an error as unallowable or impermissible due to strict standards or expected accuracy in the context.
Подобная ошибка в расчетах считается непозволительной.
Such an error in the calculations is considered unacceptable.
In this sentence, 'непозволительное' conveys the idea that making such a purchase transcends what is financially manageable or acceptable.