Dispatch spymaster on the way (8)
I believe the answer is:
transmit
'dispatch' is the definition.
(thesaurus)
'spymaster on the way' is the wordplay.
'spymaster' becomes 'm' (in James Bond).
'on' is an insertion indicator.
'the way' becomes 'transit' (I can't justify this - if you can you should give a lot more credence to this answer).
'm' put within 'transit' is 'TRANSMIT'.
Can you help me to learn more?
(Other definitions for transmit that I've seen before include "Send from one place to another" , "Send from one person to another, or broadcast" , "Send - communicate" , "Broadcast (a signal)" , "Pass on (message)" .)