Aikido ABC - Vol 3. Advanced techniques

Kaiten-nage: rotation throw.

Uke grabs one wrist from Guyaku-hanmi, we lift up his arm and dive underneath spinning and turning while spiralling and cutting down. Stepping back catching his wrist as you bring the large circular motion back up. Cut down his head and step in through the centre line and throw.
Kaiten 回転 ‘rotation’. As you can see by its character (Kanji) points to the axis along your limbs, like seen in a crosscut of the bone enclosed by the flesh (a square inside a larger square), highlights the rotation of the arms, legs and torso and not the big circular motion made by the arms.

Ten-chi nage: Heaven Earth throw. One hand up and one hand down. Spiral up and spiral down. As uke grabs your both wrists you slide outside his forward leg. Zigzag out and then back in behind his leg, trapping it with your hip. Upper hand spirals up and passed his shoulder/neck, turning inwards down as you throw him to the ground. Lower hand dives in behind ukes back, supporting and clamming his arm. Upper hand/arm catches ukes chin and throat, rotating over.

Kotegaeshi, wrist turning technique. Make sure your body makes the movements and not only your arms. Make sure not just to bend the wrist, but elbow and body as well. Step behind uke as you throw, unbalancing his whole body and not only twist his arm.

Shihonage - four direction throw. The four directions refer more to the cardinal points of north south east and west, meaning an all-around awareness. And just as Tenchinage emphasis the vertical up and down dual opposing spirals, Shihonage points to the ‘Aiki-cross’ of both the vertical and horizontal lines through the body, enabling you to turn in all directions.

From Saito Sensei’s Traditional Aikido:

Standing: Katate-dori (One-hand hold) Shiho-nage (Four-corner throw)

“Omote-waza: Open the fingers of your held hand and send your centralized energy through your finger-tips. Slide into the side of your partner from a reverse oblique stance and assume a mutual oblique stance. Grasp your partner's wrist, swinging both your arms up to the apex of their height, and turn your body as you cut him down straight. It is wrong to pass under the arm of your partner and swing your arms down in a cutting motion out of alignment with the center of your body. Inadequate turning of your body is also dangerous because it could cause a broken arm to your opponent.”

Irimi means to enter. Enter into the engagement as contrasted with Tenkan, turning. Both obviously take part in the full scale of all techniques but Iriminage highlights the entering aspect in the basic forms.

Saito Sensei on Irimi Technique.

This was considered to be is a secret technique to escape from multiple attackers. The other name for this is "Yamabiko-no- michi", the path of an echo. As you extend your Ki, the Ki of your opponent will return to you like an echo. However, you do not receive your opponent's Ki because you have instantly moved past him to his rear.

Oral Instruction from O Sensei

“Brandishing his sword, My enemy in front Prepares to attack. But behind him, I am already standing.”

“Many enemies Surround me In attack. Thinking of them as one, I do battle.”