noun
covered drain; culvert
Refers to a drain or water channel that is covered, often underground or beneath a surface, used in construction or civil engineering contexts.
道路の下に伏せ樋を設置して雨水を流す。
A covered drain is installed under the road to carry rainwater.
暗渠 is a more general term for an underground conduit or culvert, while 伏せ樋 specifically suggests a covered drain or channel, often smaller in scale.
Compound of 伏せ (fuse, 'covered' or 'hidden') and 樋 (doi, 'conduit' or 'pipe'). The spelling 伏樋 is a variant without okurigana.