This is the 9918th most frequent Japanese word.
謝り
Apology.
Here, "謝り" is part of the expression "謝りながら," where "謝る" is a verb meaning "to apologize." The phrase constructs a simultaneous action of apologizing while doing something else.
謝りながら、彼は真実を話しました。
While apologizing, he spoke the truth.
Here, "謝り" is used as a noun meaning "apology." It refers to the act of apologizing or the expressed statement of regret.
彼の謝りは心からのものだった。
His apology was heartfelt.
In this context, "謝り" again acts as a noun meaning "apology," showing it as something tangible that can be addressed or refused.