Middle English bilden, from late Old English byldan "construct a house," verb form of bold "house," from Proto-Germanic *buthla- (source also of Old Saxon bodl, Old Frisian bodel "building, house"), from PIE *bhu- "to dwell," from root*bheue- "to be, exist, grow." Rare in Old English; in Middle English it won out over more common Old English timbran (see timber). Modern spelling is unexplained. Figurative use from mid-15c. Of physical things other than buildings from late 16c. Related: Builded (archaic); built; building.
In the United States, this verb is used with much more latitude than in England. There, as Fennimore Cooper puts it, everything is BUILT. The priest BUILDS up a flock; the speculator a fortune; the lawyer a reputation; the landlord a town; and the tailor, as in England, BUILDS up a suit of clothes. A fire is BUILT instead of made, and the expression is even extended to individuals, to be BUILT being used with the meaning of formed. [Farmer, "Slang and Its Analogues," 1890]
"style of construction," 1660s, from build (v.). Earlier in this sense was built (1610s). Meaning "physical construction and fitness of a person" attested by 1981. Earliest sense, now obsolete, was "a building" (early 14c.).