This Dictionary of Japanese Martial Arts Terms is intended to further the understanding of Students. If you wish to contribute additional terms please email us and animo@toyama-ryu.com.
| Rōmaji | Kanji | Description |
| Iai | 居合い; 居合 | Drawing and cutting with the sword |
| Iaidō | 居合道 | The Japanese art of drawing the sword. |
| Iaigoshi | 居合い腰, 居合腰 | Step forward with the right foot and backwards with the left foot going into the proper sword posture. |
| Iaihiza | 居合膝 | Seated posture with right knee raised, sitting on left foot |
| Iaijutsu | 居合術 | Methods of drawing and cutting with the sword |
| Iainuki | 居合い抜き | While on one knee, drawing a sword and slashing one's opponent |
| Iaito | 居合刀 | Unsharpened metal practice sword |
| Ibuki | 息吹 | Breath. |
| Ichi | 一 | One, 1. (hitotsu) |
| Ichi Mon Ji | 一文字 | Straight line |
| Idori | 居取り | Seated techniques. |
| Iie | 否 | No |
| Ikebana | 生花 | The Japanese art of flower arrangement. |
| Iki | 息 | Breath, tone. |
| Iki No Ne | 息の根 | Life. |
| Ikkōnoken | 一口の剣 | A sword |
| Ikkyō | 一教 | First lesson, an aikido technique. (ude osae) |
| Ikkyu- | 一級 | First kyu, highest beginner grade. |
| Intoku | 陰徳 | Secret charity |
| Iori | 庵 | The top line of the mune. |
| Iori mune | 庵棟 | Mune with two surfaces |
| Ippon | 一本 | One (hon is counter for elongated, cylindrical objects), a full point. |
| Ippon Seoi Nage | 一本背負投 | One arm shoulder throw. |
| Ippon Shōbu | 一本勝負 | 1 point match, first point wins match. |
| Irimi | 入身 | Entering. |
| Irimi Issoku | 入身一足 | Enter with a single step. |
| Irimi Nage | 入身投 | Entering throw. |
| Ishin Denshin | 以心伝心 | Heart to heart, telepathy, direct transmission. |
| Isshin Ryu- | 一心流 | A style of Okinawan karate. |
| Issho | 一緒 | At the same time, together, one thread. |
| Issoku | 一足 | A pair, a step. |
| Ito | 絃 | Silk or cotton hilt wrapping cord |
| Ittō | 一刀 | Sword blade; Single stoke. |
| Ittō Dodan | 一刀土壇 | Single stoke execution |
