Scenario:
The teams cannot be named by the feature they are working on, because it will be multiple features, and feature needs change. Naming teams by numbers or letters doesn't feel correct, because it implies order or sequence.
How does one name the teams? If you were a developer on one of these teams, how would you want your team identified?
You can't have names that are both meaningful and meaningless - i.e. they help identify something organizationally but will still make sense when the organization changes.
I recommend meaningless: animals, astronomical objects, or other vague code words. That way you can record them on lists as needed but people can also use them to form mental associations. Think of what "Amazon" and "NewEgg" mean even though they don't actually mean those things.