A "visiting critic" refers to someone who is not a regular member of a certain group or organization, but visits for a specific period of time to provide evaluation, feedback, or commentary on a particular subject or topic. Full definition
She has also taught as visiting critic at Yale University. (pratt.edu)
He taught briefly at the University of North Carolina and served as visiting critic in painting at Yale University in 1964. (americanart.si.edu)
[1] He taught at Yale Graduate School of Art, first as visiting critic in art, invited by Jack Tworkov, and then as Professor of Art. (en.wikipedia.org)