Stock
Stock turns up in 2 fields: automotive, maritime. Here is what it means to the people in each one.
Stock in automotive
A vehicle or component that remains exactly as it was manufactured, with no aftermarket modifications.
Describing a vehicle, engine, or part that retains its original factory specifications. In repair and tuning, a stock baseline is the reference point before adding performance parts or custom tuning. Mechanics often prefer working on stock vehicles because the wiring and mechanical tolerances match the factory service manuals.
"The customer claims it's a stock block, but I can see an aftermarket intake manifold and headers."
Stock in maritime
The heavy wooden or steel framework that supports a ship during construction.
The structural cradle, usually built on a slipway, that holds a vessel's keel and hull in place while it is being built. The stocks bear the massive weight of the ship and keep it perfectly aligned until it is ready to be launched into the water. The term also refers to the crossbar of a traditional anchor that forces the flukes to dig into the seabed.
"The new ferry has been on the stocks for six months and is finally ready for painting."