reinforcement bar; rebar
Technical term used in construction and civil engineering for steel bars embedded in concrete to increase tensile strength.
この建物の基礎には補強筋が使われている。
Reinforcement bars are used in the foundation of this building.
Compound of 補強 (reinforcement) + 筋 (bar, rib). The exact historical derivation is uncertain; the term is a modern technical coinage.