It's the informal version of "ponimaete" (meaning "you understand") and is commonly used in everyday speech.
Here are some examples of how it's used:
* "Ponimaesh?" (Do you understand?)
* "Ya tebya ponimaesh." (I understand you.)
* "Net, ya ne ponimaesh." (No, I don't understand.)
It's important to note that "ponimaesh" is a more informal way to say "understand" and might not be appropriate in all situations.