"Rain cloud" is a common term used to describe a cloud that contains precipitation. However, there are several other synonyms that can be used to describe this type of cloud. One example is "storm cloud," which is a cloud that contains high levels of moisture and often results in thunderstorms or heavy rainfall. Another synonym is "nimbus cloud," which is a cloud that is dark and gray in color and often associated with rain or thunderstorms. A third synonym is "cumulonimbus cloud," which is a towering cloud that can produce lightning, thunder, and heavy precipitation. Using these synonyms can help add diversity and specificity to descriptions of weather conditions.