noun
horizontal moat; horizontal trench
A moat or trench dug horizontally, often in the context of Japanese castle fortifications. Contrasts with 竪堀 (たてぼり), a vertical trench.
See also: 竪堀
城の周囲には横堀が巡らされていた。
A horizontal moat was dug around the castle.
横堀と竪堀を組み合わせて防御を固めた。
They strengthened the defenses by combining horizontal and vertical trenches.