There appears to be some overlap in the use of the movie-rating tag with some users using it for content ratings (as in MPAA rating/content certification) while others are using it for questions on star ratings (as in IMDb and critic rating). The tag's wiki states that it is to be used for content ratings.
How can this ambiguity be resolved?
Why not use an unambiguous tag such as age-rating which cannot be misinterpreted as a tag about the quality or people's opinion of the movie? The MPAA and the BBFC, for example, base most of their rating judgements on what is appropriate for a particular age range (thought the MPAA is a good deal less clear and more annoying than the BBFC).
The tag movie-rating is inevitably ambiguous and will only be understood by those who read the full tag explanation (and so is likely to be missed by some however you define it). Replace it with an unambiguous term and deprecate the old usage.
It can only be resolved by us actively editing the questions and separating the meanings - perhaps creating a censorship tag for MPAA (or other national censoring organization) questions.
Gosh, its quite hard to discuss this across several days with several people. I'm going to create this answer and encourage people to comment and edit to arrive at collections of synonymous tags. Suggested lead tag shown first:
Please add or remove or re-group these - but please add comments as you do so, so people can see your argument and return them if there is disagreement. I've started with a suggestion, but honestly I'm not that enamored of movie-rating.
Meaning: classification or certification of a movie by some national or regional body, e.g. MPAA, BBFC, CBFC:
content-rating: age-rating, classification, certification
Meaning: a system of reviewing the quality of a movie through numeric score, stars or similar:
