Smile upon is a colloquial term meaning to approve or show favor to someone or something. There are several synonyms for this phrase, such as look kindly on, regard with approval, favor, or bless. Other alternatives include approve of, endorse, sanction, accept, or support. These phrases convey a sense of positivity and indicate that someone or something is viewed in a positive light. By using these synonyms, you can add more depth and nuance to your writing or conversation. They allow you to express your opinion or attitude towards a particular person or situation in a more precise and articulate manner.