How do I change my Mac's Bluetooth name?
Your Mac's Bluetooth name is visible to all and sundry, and by default includes your name and the type of Mac you own. For various reasons you might not want it to include this information - or you might want to include a witty joke, as some people do with their Wi-Fi routers.
In any case, it's very straightforward to change your Mac's Bluetooth name, although the option where you change this is hidden in a section of System Preferences where you might not have thought to look. It isn't under the Bluetooth section. Here's how to give your Mac a new Bluetooth name.
1. Open System Preferences.
2. Select Sharing. It's on the third row, with an icon that looks like a road sign.
3. Your Mac's Bluetooth name will be the same as its 'Computer Name', which is at the top of this menu. Click that field and triple-click to select the whole name (or just delete the bits you want to replace), then type in whatever you like. (Changing the Computer Name also changing the access address that your Mac occupies on the local network.)
4. There's no 'save' button - just click off the name field and the change will take effect.
If you go back and open the Bluetooth section of System Preferences, you'll see, on the left, the name under which your Mac is discoverable over Bluetooth - and sure enough, our modified name is there.
How to change the Bluetooth name for your accessories
Oddly enough, if you want to pick a new Bluetooth name for your keyboard, mouse or trackpad, you do change this via the Bluetooth section of System Preferences.
Open System Preferences and select Bluetooth - it's just to the left of the Sharing icon on the third row. Look for the device whose name you want to change: Right-click (or Ctrl-click, if you've not got a right-click on your mouse) the device's name, select Rename, then type a new name. Click Rename again. (This only works on devices that you've paired with, for obvious reasons.)