The term "moaning Minnie" is often used to describe someone who is constantly complaining or whining. However, there are various synonyms you can use to avoid using the same term repeatedly. For example, you can refer to someone as a "whinger", "crybaby", or "grumbler" if they continually moan or whine. Another option is to call them a "naysayer" or "faultfinder," denoting a person who always looks for negative aspects to criticize. When someone frequently complains about trivial issues, they may also be known as a "nitpicker" or "fusspot". Using these synonyms can help you avoid using the same term when describing someone who frequently moans or complains.