component
adj[C] Countable
pl: components
This word evokes a sense of modularity and precision. It suggests that the part is not just a random piece, but a designed element that serves a specific function within a larger system. If you remove a component, the entire machine or process typically fails or loses significant capability. While a part can be any piece of something, a component implies a technical or structural relationship. It is frequently used in engineering, electronics, and software development to describe building blocks that can be swapped, upgraded, or integrated.
Countable when referring to individual physical parts like a capacitor in a circuit or a specific ingredient in a chemical mixture.