Glossary /// Alias
Straitjacket armbar
Also known as Back Armbar — the canonical term used on this site.
Training background: Names the control that isolated the arm, which is the more precise label
Descriptive — names the control that isolated the arm
Straitjacket armbar names the back armbar by the control that made it possible: arm-trapped back control, with the defender’s near arm pinned across their own body.
Etymology. It is the more precise of the two common names because it says which back control is meant. Plain back control does not produce this attack — without a trapped arm there is nothing isolated to take, and the submission degrades to a gift of the position. Naming the straitjacket names the prerequisite.
Mechanics. The isolation is inherited rather than built, which is unique in the armbar family: the straitjacket exists to make a strangle inescapable, and the armbar is what becomes available when that control begins to fail. So the attack is read rather than set up, and the honest rule for when to take it is when the strangle has gone rather than when the arm looks tempting — the two are evidence of the same thing and only one is a reason.
Cross-reference. The control itself is on Straitjacket. Full mechanical coverage on Back Armbar.