To settle, finish, or bring something to an end (transitive expression meaning to put an end to a matter).
この問題にけりをつけるために、会議を開いた。
We held a meeting to settle this issue.
彼はやっと前の仕事にけりをつけて、新しい職場に移った。
He finally wrapped up his previous job and moved to a new workplace.
双方で話し合い、けりをつける方法を見つけた。
Both sides talked and found a way to settle things.