This is the 19284th most frequent Korean word.
않겠느냐
"않겠느냐" means "won't (you/it)?" or "wouldn't (you/it)?"
Used as a suggestion or proposal by asking if one would not do it, suggesting a willingness or option.
오늘은 함께 공부를 하지 않겠느냐?
How about studying together today?
Used to inquire about another's willingness or availability to perform an action.
그는 도와주지 않겠느냐고 물었다.
He asked if you would not help.
Used rhetorically to suggest waiting or expect someone's action, forming a polite or considerate proposal.