He needs to get a letter half dictated (6)
I believe the answer is:
addict
'he needs to' is the definition.
The answer is a person as well as being a singular noun. This is suggested by the definition.
'a letter half dictated' is the wordplay.
'letter' becomes 'd'.
'half' indicates taking half.
'dictated' cut in half is 'dict'.
'a'+'d'+'dict'='ADDICT'
'get' is the link.
Can you help me to learn more?
(Other definitions for addict that I've seen before include "Drug dependant" , "aficionado" , "Slave to a chemical substance" , "Someone who's hooked?" , "Regular drug user" .)