Eastern books on article in window (8)
I believe the answer is:
oriental
'eastern' is the definition.
(similar in meaning)
'books on article in window' is the wordplay.
'books' becomes 'nt' (abbreviation for New Testament).
'on' indicates putting letters inside.
'article' becomes 'a' (the indefinite article in English).
'in' means one lot of letters goes inside another.
'window' becomes 'oriel' (oriel window is a kind of window).
'a' inserted into 'oriel' is 'orieal'.
'nt' inserted inside 'orieal' is 'ORIENTAL'.
(Other definitions for oriental that I've seen before include "from Japan, say" , "Filipino, for example" , "Eastern {8}" , "Korean, for example" , "Relation of far eastern type" .)