Art authority is a term used to describe a person or institution that is considered an expert in the field of art. However, there are several antonyms for this word that could be used to describe individuals or institutions that have little or no knowledge in this area. These antonyms include amateur, novice, layperson, non-specialist, non-professional, and dilettante. Using these antonyms, one could describe a person who has a general interest in art but has not studied it formally, or an institution that lacks the expertise or resources to be considered an authority in the field.