When someone "fawns over" someone else, it usually means they are being excessively adoring or flattering towards them. There are several synonyms for this phrase, including grovel, kowtow, flatter, butter up, and brown-nose. All of these words have a negative connotation, suggesting the person is being insincere or manipulative in their behavior. Other synonyms for "fawns over" include gush, gloat, idolize, and worship, although these tend to have a more positive connotation, suggesting the person truly admires or loves the other individual. Overall, the phrase "fawns over" is often used to describe behavior that is either overly submissive or insincerely complimentary.