She is reviewing article material (7)
I believe the answer is:
hessian
'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 don't see?
'she is reviewing article' is the wordplay.
'she' becomes 'hes' (I can't explain this - if you can you should believe this answer much more).
'reviewing' is a reversal indicator (I've seen 'reviewed' mean this).
'article' becomes 'an' (indefinite article).
'is' backwards is 'si'.
'hes'+'si'+'an'='HESSIAN'
Can you help me to learn more?
(Other definitions for hessian that I've seen before include "sackcloth?" , "Cloth made from jute" , "Cloth for sacking" , "Coarse fabric used in sacks" , "Coarse cloth" .)