Where one might keep a record of type of timber needed, as well as volume? (7)
I believe the answer is:
logbook
'where one might keep a record of type of timber' is the definition.
Although both the answer and definition are singular nouns, I can't see how one could define the other.
'needed as well as volume?' is the wordplay.
'needed' becomes 'log' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'as well as' says to put letters next to each other.
'volume?' becomes 'book' (synonyms).
'log'+'book'='LOGBOOK'
Can you help me to learn more?
(Other definitions for logbook that I've seen before include "Ship's record" , "Former vehicle document" , "Incident-recording volume" , "Registration paper" , "Car owner's document" .)