Speech by Ray ruined book (10)
I believe the answer is:
dictionary
'book' is the definition.
(dictionary is a kind of book)
'speech by ray ruined' is the wordplay.
'speech' becomes 'diction' (diction is someone's way of speaking).
'by' is a charade indicator (letters next to each other).
'ruined' is an anagram indicator.
'ray' is an anagram of 'ary'.
'diction'+'ary'='DICTIONARY'
(Other definitions for dictionary that I've seen before include "reference work" , "Work full of meaning" , "Where to find the meaning of life, for example!" , "Brewer's creation, say" , "Ordered book" .)