1768, "to build anew," from re- "back, again" + construct (q.v.). Meaning "to restore (something) mentally" is attested from 1862. Reconstruction is attested from 1791, "action or process of reconstructing. Specific sense in U.S. history (usually with a capital R-) is attested from 1865. It was used earlier during Amer. Civil War in ref. to reconstitution of the union.