You can create tags since you have (way) more than 300 reputation. The question is: should you? This is what the help center says:
When should I create new tags?
Most common tags already exist on a mature site. You should always favor existing tags; only create new tags when you feel you can make a strong case that your question does cover a new topic that nobody else has asked about before on this site.
IMHO the word-choice tag already covers this (especially when combined with modal-verbs):
This tag is for questions which a dictionary cannot answer about the several possibilities available for a particular meaning, and which one of them would be the most appropriate.
so I would advise against creating a new tag for this.
I do know I'm quite conservative when it comes to tags (across the Stack Exchange network): just because you can add five tags to a question doesn't mean you should. I'm interested in what others have to say about this.