French coinage from 1875: Latin 'infra' (below) + 'structura' (structure) — originally a railroad term for track foundations.
The basic physical and organizational structures and facilities needed for the operation of a society or enterprise, such as roads, power supplies, and communications networks.
From French 'infrastructure' (1875), composed of Latin 'infrā' (below, beneath, underneath) + 'strūctūra' (a fitting together, a building, a construction), from 'struere' (to pile up, to arrange, to build), from PIE *strew- (to spread, to strew, to scatter). Originally a precise French civil-engineering term for the foundational earthworks beneath railroad tracks — the embankments, cuttings, tunnels, and drainage that support the visible 'superstructure' of rails and sleepers above. French military engineers adopted it for the underlying
The word 'infrastructure' was virtually unknown to the general public before the 1980s. It originated as a French railroad engineering term in 1875 for the earthworks underneath train tracks (the 'structure below'). NATO adopted it in the 1950s for military installations, and it entered general English during policy debates about crumbling American roads and bridges