If you look at the definitions I linked to, you'll see that they are very similar to each other and both involve a lot more than "just means you can view the code".
In fact, the very first sentence of the introduction explicitly rejects your proposed definition: "Open source doesn't just mean access to the source code."
In fact, the very first sentence of the introduction explicitly rejects your proposed definition: "Open source doesn't just mean access to the source code."