Instructions from this teacher given at volume (9)
I believe the answer is:
guidebook
'instructions' is the definition.
The answer and definition can be both related to communication as well as being singular nouns.
Maybe there's a link between them I don't understand?
'this teacher given at volume' is the wordplay.
'this teacher given' becomes 'guide' (I can't explain this - if you can you should give a lot more credence to this answer).
'at' is a charade indicator (letters next to each other).
'volume' becomes 'book' (synonyms).
'guide'+'book'='GUIDEBOOK'
'from' is the link.
Can you help me to learn more?
(Another definition for guidebook that I've seen is " Source of information for tourists".)