Brief history

"The purpose of this art is not to be killed, not to be struck, not to be kicked, and we will not strike, will not kick, and will not kill. It is completely for self-defense. We can handle opponents expediently, utilizing their own power, through their own aggression. So even women and children can use it. However, it is taught only to respectable people. It's misuse would be frightening..."
— Sokaku Takeda.
First is Zanshin
The kanji "zan" and "shin" can be read in two ways. Kokoro-Wo-Nokosu, which means, "I consciously do the action of getting my spirit to remain" and Kokoro-Ga-Nokoru, which means, "My spirit remains unconsciously, spontaneously." Zanshin, thus means that one is always prepared, even when exhausted, and even when the confrontation is over, the spirit remains. So, Zanshin is a state of constant awareness that will allow the trained budoka to maintain "perfect timing."
Second is Ai
The kanji character means blending or harmonizing. It is pronounced as "AI" in Japanese.
Third is Ki
This kanji character means energy, and is pronounced "KI" in Japanese. It is believed that everything in the Universe, material or not, was ultimately derived from sound energy. Consequently, one should be able to master the ability to control his energy, and harmonize it with the surrounding energy.

Aiki emphasizes "an early neutralization of an attack," using the timing of that attack to either blend with it, or neutralize its effectiveness, and use the force of the attackers’ movements against them.

So, (when mastered) zanshin, ai, and ki (like three streams) blend together to form a river, that with time, effort, and the addition of other important skills, becomes a true budo, named AIKIBUDO
That's why the name "THREE STREAMS AIKIDO" was chosen for newly established in the year 2000 Dojo, that at later date was changed to "THREE STREAMS AIKIBUDO" , which was better and a more complete reflection of the actual curriculum of Martial Arts being taught here.