Suitable space covered with banks of modernist furniture (7)
I believe the answer is:
fitment
'furniture' is the definition.
(fitment is a kind of furniture)
'suitable space covered with banks of modernist' is the wordplay.
'suitable' becomes 'fit' (similar in meaning).
'space' becomes 'en'.
'covered with' is an insertion indicator.
'banks of' means to remove the middle letters (the banks are the sides of the word).
'modernist' with its centre removed is 'mt'.
'en' put into 'mt' is 'ment'.
'fit'+'ment'='FITMENT'
(Other definitions for fitment that I've seen before include "piece of furniture" , "fixture" , "Item of (built-in) furniture" , "Permanent item of furniture or equipment" , "Fixed item of furniture" .)