I entered the following command:

/give username* bow{display:{Name:"random name"}}

*username is where my username would go.

It didn't work. No matter how many times I tried (with all sorts of different names), it would still be called "bow" (the default name for bows). However, when I put this in:

/give username* bow{display:{Name:"12312"}}

it somehow started working. It also worked with any positive integer or decimal number, but no letters. (I didn't get to try negative numbers, because after accidentally leaving the name blank it subsequently crashed and corrupted the world.)