It's of some rough material (3)
I believe the answer is:
mat
'material' is the definition.
The definition and answer can be both man-made objects as well as being singular nouns.
Perhaps you can see an association between them that I can't see?
'it's of some rough' is the wordplay.
'it' becomes 'ma' (I can't explain this - if you can you should believe this answer much more).
'of some' says to take the centre (I've seen 'some' mean this).
'rough' becomes 'sketchy' (both can mean vague).
The centre of 'sketchy' is 't'.
'ma'+'t'='MAT'
Can you help me to learn more?
(Other definitions for mat that I've seen before include "coaster" , "Not glossy" , "dull finish" , "Shoe-cleaner" , "To wipe your feet on" .)