Woeful enjoyment before a library's opening (8)
I believe the answer is:
funereal
'woeful' is the definition.
(thesaurus)
'enjoyment before a library's opening' is the wordplay.
'enjoyment' becomes 'fun' (I've seen this before).
'before' becomes 'ere' (usually literary**).
'opening' says to take the initial letters.
The initial letter of 'librarys' is 'l'.
'fun'+'ere'+'a'+'l'='FUNEREAL'
(Other definitions for funereal that I've seen before include "Of the ritual of the dead" , "Gloomy" , "Of sombre character" .)