In a cam-in-block engine the part of the valve train riding directly in the camshaft is the?

In a cam-in-block engine, the part of the valve train that rides directly on the camshaft is called the lifter or tappet. The lifter translates the rotational motion of the camshaft into vertical movement, which then actuates the pushrod (in pushrod engines) or directly opens the valve (in overhead cam designs). This mechanism is crucial for controlling the timing and operation of the engine's intake and exhaust valves.