Defenses and variations of techniques

Nage/Tori

These two terms describe the defender (the individual applying the technique).  Nage means to throw and Tori means to execute the technique.  The two terms are more or less interchangeable.  Even when the technique isn't a throw, the term nage is still often used.

Defenses

Below is a list of the most common techniques we practice. It is intended to be a simple reference for beginners, therefore descriptions are brief.

Ikkyo (first principle) - hold the attacking arm at the wrist and elbow.
Nikyo (second principle) - using ikkyo as a foundation, fold the wrist and control the elbow, applying pressure downward.
Sankyo (third principle) - using ikkyo as a foundation, twist the attacker's wrist up in a spiral motion.
Yonkyo (fourth principle) - using ikkyo as a foundation, apply pressure on the pressure point on the inside of the attacker's wrist.
Gokyo (fifth principle) - using ikkyo as a foundation, fold the attacker's wrist. Designed to disarm an attacker with a knife.
Iriminage (entering throw) - throw the attacker backwards using your arm under his/her chin.
Sokumen Iriminage
(sideways facing entering throw) - throw the attacker backwards using your arm under his/her chin while facing sideways.
Shihonage (four directions throw) - fold the attacker's wrist back past the shoulder, locking the shoulder.
Kokyunage (breath throw) - throw your partner focusing on generating power by exhaling.
Kotegaeshi (wrist reversal) - throw your partner by twisting their wrist outwards.
Kaitennage (spinning throw) - throw your partner holding their head down and arm up.
Tenchinage (heaven & earth throw) - throw your partner by separating your hands - one arm extends down and the other extends up.
Tenbinnage (see-saw throw) - throw your partner with one arm under the elbow.
Aikiotoshi (harmonizing energy drop) - throw your partner by dropping just before they strike.
Udekime (arm control) - control the attacker by wrapping both arms around theirs.
Koshinage (hip throw) - throw the attacker over the hip.
Jujigarami (cross throw) - lock up the attacker's arms in a cross configuration and then throw.
Henka Waza (changing techniques) - switching from one technique to another.
Kaeshi Waza (countering techniques) - countering the technique of the opponent.
Fuiuchi Taisho Waza (unconventional techniques) - a category of techniques where attacks are unconventional. Designed to allow aikido responses to be applied to any type of attack.

Exercises

While techniques have the element of attack and defense, exercises do not. The partner being held is working to coordinate the power of the physical body with the breath (ki) while the one holding is maintaining the most sincere connection possible.
Kokyuho (breathing method) - an exercise designed to coordinate your breathing with the movement of the body
Kokyudosa (breathing exercise) - a seated exercise where both partners remain well connected while the one being held off-balances and pins the other

Variations of Techniques

Aikido techniques have variations, which put you in front or behind your partner. There are also variations, which put you either inside or outside of the attack.

Omote waza (front variation) - a variation that puts you in front of you partner
Ura waza (rear variation) - a variation which puts you behind your partner
Uchi mawari (moving inside) - a variation that puts you inside of the attack
Soto mawari (moving outside) - a variation that puts you outside of the attack