Boatman follows core of convoluted book (6)
I believe the answer is:
volume
'book' is the definition.
(synonyms)
'boatman follows core of convoluted' is the wordplay.
'boatman' becomes 'me' (I can't justify this - if you can you should give a lot more credence to this answer).
'follows' says to put letters next to each other.
'core of' means to look at the middle letters.
The centre of 'convoluted' is 'volu'.
'me' after 'volu' is 'VOLUME'.
(Other definitions for volume that I've seen before include "work" , "Magnitude of sound" , "Tome" , "Book; degree of loudness" , "reading matter?" .)