A defensive obstacle made of felled trees with sharpened branches facing outward, used historically in Japanese fortifications. Rare in modern contexts; mainly encountered in historical or military descriptions.
Abatis were set up around the castle to prevent enemy intrusion.
Compound of 逆 (saka, 'reverse, opposite') + 茂木 (shigeki, 'thick growth of trees'), referring to trees placed with branches reversed to form a barrier. The exact historical derivation is uncertain.