Takemusu

Aikido concepts are ideas that form the philosophical or technical basis of the Japanese martial art aikido.

Aiki means the defender blends without clashing with the attacker, then goes on to dominate the assailant through the application of internal strength or Ki energy to effect techniques. Blending with an attacker's movements allows the Aiki practitioner to control the actions of the attacker with minimal effort.

Hanmi (半身) means "half body". The idea that the sides of the body work as a unit (for example: left hand and left foot forward). Usually, though not exclusively, descriptive of the movement in Aikido. Closely related to the development of Chushin-ryoku.

Often used to refer to the triangular stance (kamae) of Aikido. Similar stances and the same word are used in other martial arts and traditional theater, including sumo and kyōgen.

Chushin-ryoku (中心力, chūshin-ryoku) means "center of power".

Chushin-sen (中心線, chūshin-sen) means "center line". The term is also associated with kendo.

Ichi-go ichi-e (一期一会, literally "one time, one meeting") describes a cultural concept often linked with tea master Sen no Rikyu. The term is often translated as "for this time only", "never again", or "one chance in a lifetime". Ichi-go ichi-e is linked with Zen Buddhism and concepts of transience. The term is particularly associated with the Japanese tea ceremony, and is often brushed onto scrolls which are hung in the tea room. In the context of tea ceremony, ichi-go ichi-e reminds participants that each tea meeting is unique.

Irimi (入り身) describes entering straight into a technique, as opposed to the more indirect entrance into technique called tenkan. Irimi usually looks like a step forward, straight or at an angle but usually ending with the body facing the attacker, rather than in the direction of the step. To enter with irimi, the defender needs to move in the very moment of the attack or even himself initiate it.

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Wikipedia