"Cumulo-cirro-stratus" is a specific cloud type, also known as a "triple-layered cloud," that is formed by the combination of three different cloud types. If you're looking for synonyms for this specific type of cloud, you might still want to consider words that describe other types of clouds. Some examples include "stratus," which is a low-lying, gray cloud that covers the sky like a blanket; "cumulus," which is a fluffy, white cloud that often resembles cotton balls; and "cirrus," which is a wispy, high-altitude cloud that often looks like feathers in the sky. Other cloud-related words that you might want to consider could include "nimbus," which means "cloud" in Latin, or "nebula," which is a term often used to describe clouds of gas and dust in space.