It's possible that this is a misspelling or a creative expression that doesn't follow typical grammar rules. To understand what it might mean, we need more context.
Could you please provide more information about where you saw this phrase?
Here are some possibilities of what it could be trying to convey:
* A metaphor: "Rock" might symbolize strength and stability, and "terrible" might refer to a difficult situation. The phrase could be a way of saying someone remained strong and resilient through a tough time.
* An idiom or slang: It's possible the phrase is a regional idiom or slang term that has a specific meaning within a particular community.
* A typo or mishearing: It's possible there's a typo in the phrase, and it's actually meant to say something else entirely.
Please provide more context, and I'll do my best to help you decipher the meaning!