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Ju-do, noun a sport of unarmed combat derived from Ju-Jitsu, using holds and leverage to unbalance the opponent. -ORIGIN Japanese, 'gentle way'.

For more information click on the Judo kenji

Karate-Do. noun an oriental system of unarmed combat using the hands and feet to deliver and block blows.
-ORIGIN Japanese, 'empty hand'.

For more information click on the Karate-Do kenji

Aiki-do, noun a Japanese form of self-defense and martial art that uses locks, holds, throws, and the opponent's own movements.
-ORIGIN Japanese, 'way of adapting the spirit'.

For more information click on the Aikido kenji

Ju-Jutsu (also Jiu-Jitsu or Ju-Jitsu), noun a Japanese system of unarmed combat and physical training.
-ORIGIN Japanese, 'gentle skill'.

Ancient martial art (from ko = ancient and budo = martial art). Also used for the minor martial arts. The diversity of these art and there use of weapon in combat and non combat situation.