Reading so liberally is quite pretentious (9)
I believe the answer is:
grandiose
'quite pretentious' is the definition.
(grandiose means pretentious or ostentatious)
'reading so liberally' is the wordplay.
'liberally' indicates an anagram.
'reading'+'so'='readingso'
'readingso' is an anagram of 'GRANDIOSE'.
'is' acts as a link.
(Other definitions for grandiose that I've seen before include "Pretentiously imposing -- organised (anag)" , "Bombastic" , "I grade son as affectedly splendid" , "affected" , "Imposing and pompous, dressed in organdies" .)