A noun used especially in grammar and linguistics for negation or a negative form; it can also describe the act or function of denying or negating a statement.
文末の「ない」は打ち消しを表す。
The sentence-final nai expresses negation.
「行かない」は「行く」の打ち消しです。
Ikanai is the negative of iku.
"Tabenai" is the negative form of "taberu."
"Nai" is a negation auxiliary verb.
Evidence emerged that negates that statement.