What does the idiom “rock solid” mean?
Definition: unbreakable, not vulnerable to change
Example: If you’re going to miss the exam, you’d better have a rock solid excuse for why you couldn’t be there.
What does the idiom “rock solid” mean?
Definition: unbreakable, not vulnerable to change
Example: If you’re going to miss the exam, you’d better have a rock solid excuse for why you couldn’t be there.