Emily Dickinson Lexicon

COR'RI-DOR, n. [Fr.; Sp. corredor, from correr; It. correre; L. curro, to run, to flow. The termination dor may perhaps be the L. tor, as in curator, cursitor. Corridor signifies a runner; hence, a running, flowing, or long line.]

1. In architecture, a gallery or long aisle round a building, leading to several chambers at a distance from each other. – Harris.
2. In fortification, the covered way lying round the whole compass of the fortifications of a place. – Harris.