1889, from Japanese judo, from ju "softness, gentleness" (from Chinese jou "soft, gentle") + do "way, art," from Chinese tao "way." "A refined form of ju-jitsu introduced in 1882 by Dr. Jigoro Kano, using principles of movement and balance, and practiced as a sport or form of physical exercise" [OED].
实用例句
1. He's a judo black belt but he says he deplores violence.