切磋琢磨：せっさたくま [se-ssa-taku-ma]

学問や人徳をよりいっそう磨き上げること。また、友人同士が互いに励まし合い競争し合って、共に向上すること。

More polished raise that academic and virtue . In addition, each other to compete each other encouragement friends with each other , to improve both things.