Diligent effort to improve oneself (study, skill, or character); self-cultivation through hard work.
学生時代、彼は毎日問題集を解き、切磋琢磨して数学の力を伸ばした。
During his student days he solved problem sets every day and diligently improved his math skills.
自分を高めるためには、切磋琢磨する姿勢が大切だ。
To improve yourself, an attitude of diligent self-cultivation is important.
武道では、技と精神を切磋琢磨することが重んじられる。
In martial arts, cultivating both technique and spirit through diligent practice is valued.
Mutual encouragement and friendly rivalry: people pushing each other to improve by practicing or competing together.
部活動の仲間と切磋琢磨しながら毎日練習している。
They practice every day, encouraging and pushing each other in the club.
彼とはライバルだが、切磋琢磨できるいい関係だ。
He's my rival, but it's a good relationship where we push each other to improve.
切磋琢磨の末にチームは大会で好成績を残した。
After much mutual effort, the team achieved good results at the tournament.