Origin and history of stock-car

c. 1300, "wheeled vehicle," from Anglo-French carre, Old North French carre, from Vulgar Latin *carra, related to Latin carrum, carrus (plural carra), originally "two-wheeled Celtic war chariot," from Gaulish karros, a Celtic word (compare Old Irish and Welsh carr "cart, wagon," Breton karr "chariot"), from PIE *krsos, from root *kers- "to run." The Celtic-Latin word also made it into Greek, as karron "wagon with four wheels."

"From 16th to 19th c. chiefly poetic, with associations of dignity, solemnity, or splendour ..." [OED]. Used in U.S. by 1826 of railway freight carriages and of passenger coaches on a railway by 1830; by 1862 of streetcars or tramway cars. The extension to "automobile" is by 1896, but between 1831 to the first decade of 20c. the cars meant "railroad train." Car bomb is attested from 1972, in a Northern Ireland context. The Latin word also is the source of Italian and Spanish carro, French char.

early 15c., "supply for future use; collective wealth;" mid-15c., "sum of money set aside for a specific purpose;" Middle English developments of stock (n.1), but the ultimate sense connection is uncertain. Perhaps the notion is of the "trunk" from which gains are an outgrowth, or from stock (n.1) in obsolete sense of "money-box" (c. 1400). Probably several different lines of development are represented here.

The meaning "subscribed capital of a corporation" is from 1610s. The figurative phrase take stock in "repose confidence in, regard as important" is from 1870, from the notion of investment.

In stock "in the possession of a trader" is from 1610s. The meaning "broth made by boiling meat" is from 1764. As "raw material from which anything is made," 1873, especially in reference to paper.

Theatrical use, in reference to a company regularly acting together at a given theater, performing recurring types, or staging a fixed set of plays, is attested from 1708, from the notion of something habitually produced or used. 

Taking stock "making an inventory" is attested from 1736. One's stock in trade in a literal sense was "goods kept on hand by a dealer or storekeeper" (1760s) with figurative use by 1784.

As the collective term for the movable property of a farm, especially horses, cattle, sheep, and other useful animals, it is recorded from 1510s; hence livestock, stockyard. "The application to cattle is primarily a specific use of the sense 'store', but the notion of 'race' or 'breed' ... has had some share in its development" [OED].