I would like to make a content type node title into a Term of reference. The titles need to be limited by some taxonomies.
How to convert Content Type Title into Term reference?
Title Field UI might work for you. I haven't used this module, but apprently it allows you to modify title fields. Not sure if it will allow you the change the type from text to term reference. Although, you can always disable titles and use another term ref field as your title.