Aikido-: The word "aikido" is made up of three Japanese characters: AI; harmony, KI ; universal energy, DO ; the Way. So the proper definition for Aikido is "The way of harmony with universal energy."
Aikikai -:"Aiki association."
Ueshiba Kisshomaru -: The son of the founder of aikido
Ueshiba Morihei -: The founder of aikido. ( see O-SENSEI and KAISO).
Ueshiba Moriteru -: The grandson of the founder and current DOSHU at HOMBU DOJO.
Aikidoka -: A practitioner of aikido.
Dojo Cho -: The head of the dojo.
Sensei -: Teacher. It is considered proper to address the instructor during practice as "Sensei" rather than by name.
Kaiso -: A title; The founder of Aikido, (Morihei Ueshiba).
Dojo -:"Place of the Way." Also "place of enlightenment." A place where people practice aikido. Bowing in the direction of the shrine often known as kamiza is required when entering and leaving the dojo.
Hombu Dojo -: A term used to refer to the central dojo of an organisation. This usually designates the Aikido World Headquarters.
Kamiza -: A small shrine, especially in an aikido, generally located the front of the dojo, and often housing a picture of the founder.
Domo Arigato Gozaimashita -: Japanese for "thank you very much." At the end of each class, it is proper to bow and thank the instructor and those with whom you've trained.
Onegai shimasu -:"I welcome you to train with me" is said whenever a new technique is to be practiced.
Ai Hanmi -: Mutual stance where uke and nage each have the same foot in front.
Gyaku Hanmi -: Opposing stance (if uke has the right foot forward, nage has the left foot forward, if UKE has the left foot forward, NAGE has the right foot forward).
Ashi Sabaki -: Footwork. Proper footwork is essential in aikido for developing strong balance and for facilitating ease of movement.
Jodan -: "Upper position," a position with hands/weapon held in a high position.
Chudan -: "Middle position," a position where hands/weapon are held in a central position in respect to ones body.
Gedan -: "Lower position," a position where hands/weapon are held in a low position.
Hanmi -: Triangular position.
Hanmi Handachi -: Position with NAGE sitting, UKE standing. Training in hanmi handachi is a good way of practicing techniques as though with a taller opponent.
Hidari -: Left hand and foot.
Migi -: Right hand and foot.
Seiza -: Sitting on one's knees. This is often useful in order to acquire strength in the legs, and it helps us get used to been closer to the ground.
Mae -: To the front. Mae ukemi (forward roll in order to avoid impact with the ground)
Ushiro -: Behind, back-wards roll Ushiro ukemi (back-wards roll in order to avoid impact with the ground)
Zanshin -: State of permanent awareness.
Chushin -: Center of one's movement or balance.
Ai Nuke -: "Mutual escape;" where each participant escapes harm.
Ai Uchi -: "Mutual kill;" where each participant kills the other.
Bokken or Bokuto -: Wooden sword. Many aikido movements are derived from traditional Japanese fencing.
Budo -: "Martial way."
Dan -: Black belt rank. White belt ranks are called KYU ranks.
Fudo Shin -: "Immovable mind," a state of mental composure or imperturbability. The mind, in this state, is calm and undistracted.
Furi Kaburi -: Sword-raising movement. This movement in found especially in ikkyo, irimi-nage, and shiho-nage.
Happo -: 8 directions; as in happo-undo.
Hara -: One's center of gravity.
Henka Waza -: Varied technique, beginning one technique and changing to another in midway.
Jiyu Waza -: Free-style practice of techniques; usually involves more than one attacker.
Kaeshi Waza -: Technique reversal; uke becomes nage and vice-versa. This is usually a very advanced form of practice. Kaeshi waza practice helps prevent the application of KAESHI. This technique greatly sharpens aikido skills.
Kami -: A divinity, living force, or spirit.
Kata -:"Shoulder."
Katame waza -:"Hold-down" (pinning) techniques.
Kensho -: Enlightenment. (mokuso)
Ki -: Energy, the force of ones intention. (Chinese = Chi, even though in Japanese chi means blood)
Ki Musubi -: The act of matching one's partner's Movements or intentions at its inception, this technique this is helpful to avoid direct contact with the opponent.
Kokyu -: Co-ordination of breath with the movement.
Kumijo -: Jo exercise with a partner.
Kuzushi -: The principle of destroying one's partner's balance.
Misogi -: Spiritual purification performed at the beginning of any lesson.
Mokuso -: Is the meditation done at the beginning of practice and at the end of practice. This serves to clear the mind and achieve a certain point of relaxation.
Nagare -: Flowing; the main purpose of Aikido is to achieve an indestructible level of movement, much like that of water. This serves as a sort of protection barrier between the attacker and the defender, there is a need for no physical or violent contact with the opponent in order to be able to practice properly.
Nage -: The person applying the technique.
Uke -: the person who receives the technique of the nage.
Omote -: "Towards the front of the opponent."
Ura -: "Towards the back of the opponent."
Shikaku -: Meaning a dead angle, where it is difficult for the attacker to continue and easy for the nage to redirect the flow of energy.
Shikko -: Knee walking, a displacement that is useful when applying hanmi handachi.
Shodan -: First degree black belt.
Suwari Waza -: Techniques performed when both nage and uke are in a sitting position.
Tachi -: Often used to describe the "normal" standing position.
Tachi Waza -: Standing techniques.
Gi or Keiko Gi -: Training costume; must be white.
Obi -: A belt worn by all students.
Hakama -: Divided skirt usually worn by black-belt ranks. In some dojo, the hakama is worn by women of any rank, and in others by all practitioners.
Irimi -: Entering movement. The idea behind irimi is to place oneself in relation to an attacker in such a way that the attacker is unable to continue his original objective, and in such a way that one is able to control the attacker's balance.
Tai Sabaki -: Body movement rotating 180 degrees creating a complete circle.
Tenkan -: movement turning the body 180 degrees.
Tenshin -: A movement where NAGE retreats 45 degrees away from the attacker, usually done at the end of each movement in order to create a gap between the two practitioners.
Shomen -: Direct strikes aimed for ones head.
Tsuki -: A punch or thrust.
Yokomen -: Strike aimed to the side of the head.
Jo -: Wooden staff about 4'-5' in length. Many jo movements come from traditional Japanese spear- fighting.
Tanto -: A dagger.
Tegatana -: "Hand sword."

The square in Aikido does not meen streangth but the sheer power to hold the opponent and not let him move from a position. This is used when Nage is performing a technique and finishes the movement by basically paralising the opponent in such a way that he cannot move.
The circle in Aikido means movement. This is necessary to be able to dodge and re-direct the opponents energy. This is always used in Aikido and it is acompanied by the square and the triangle.
The triangle is the basis of Aikido. It is the flow of energy. Which is why whenever a tecnique is about to take place, a person starts out in Hidari Kamae, or Migi Kamae(look in definitions)