Attendant needing coal yet to be moved (7)
I believe the answer is:
acolyte
'attendant' is the definition.
(thesaurus)
'coal yet to be moved' is the wordplay.
'to be moved' indicates anagramming the letters.
'coal'+'yet'='coalyet'
'coalyet' is an anagram of 'ACOLYTE'.
'needing' is the link.
(Other definitions for acolyte that I've seen before include "Religious assistant" , "Altar boy" , "Faithful assistant" , "Devoted follower" , "Attendant - faithful follower" .)