Nothing in striking description that's solid? (3-3)
I believe the answer is:
all-out
'nothing in' is the definition.
Both the answer and definition are adjectives. Perhaps you can see an association between them that I can't see?
'striking description that's solid?' is the wordplay.
I cannot quite understand how this works, but
'striking' could be 'out' (striking out is a common phrase) and 'out' is located in the answer.
The remaining letters 'all' is a valid word which might be clued in a way I don't see.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for all-out that I've seen before include "Using full strength or energy - nobody home?" , "Thorough-going" , "Complete" , "Whole-hearted (effort)" , "Using every resource" .)