Resting Bitch Face (RBF) is a term used to describe a person's neutral facial expression that appears unfriendly, annoyed, or unapproachable. While the term is commonly used, it is considered derogatory towards women and is not an appropriate way to describe someone's appearance. There are many synonyms that can be used instead of RBF, including neutral expression, serious face, stone-faced, poker-faced, blank expression, or unsmiling. Using these terms instead of RBF helps to eliminate the negative connotations associated with the term and promotes a culture of kindness and respect towards others' appearances. Remember, it's not okay to use derogatory terms to describe someone's appearance or behavior.