Alias · Guard
Back X
Also known as Ushiro X — Reverse X Guard — the canonical term used on this site.
Training background: colloquial
Colloquial — ushiro X guard
Back X is the colloquial English-translation name for ushiro X — the reverse/back-facing variant of the X-guard configuration where the bottom player hooks are reversed relative to standard X-guard.
Etymology. “Back” renders the Japanese ushiro (“rear” or “back”) into English; “X” carries the leg-configuration name forward. The label predominates in coaching contexts that prefer English to the Japanese.
Mechanics. The reversed hook configuration provides leverage angles distinct from standard X-guard — the back-facing geometry opens back-take and inversion entries.
Cross-reference. Ushiro X is the Japanese name. Full mechanical coverage on Ushiro X.