(Japanese: “way of spiritual harmony”), self-defense system that resembles the fighting methods jujitsu and judo in its use of twisting and throwing techniques and in its aim of turning an attacker's strength and momentum against himself. Pressure on vital nerve centres is also used. Aikido was developed to subdue, rather than maim or kill as in jujitsu and karate, but many of its movements can nevertheless be deadly. Aikido especially emphasizes the importance of achieving complete mental calm and control of one's own body to master an opponent's attack. As in other Oriental martial arts, the development of courtesy and respect is an integral part of aikido training.

The basic skills of aikido probably originated in Japan in about the 14th century. In the early 20th century they were systematized in their modern form through the work of the Japanese martial-arts expert Ueshiba Morihei. There are no offensive moves in aikido. As taught by Ueshiba, it was so purely defensive an art that no direct contest between practitioners was possible. Later a student of Ueshiba, Tomiki Kenji, developed a competition style (known as Tomiki aikido) that incorporates aikido techniques. A competitor attempts to score points by swiftly touching an opponent with a rubber or wooden knife, and the other tries to avoid and disarm the attacker. The two alternate in wielding the knife. See also martial art.