Gospel writer's letters (5)
I believe the answer is:
marks
'letters' is the definition.
The definition and answer can be both related to communication as well as being plural nouns.
Perhaps there's a link between them I don't understand?
'gospel writer's' is the wordplay.
'gospel' becomes 'Mark' (Gospel of Mark).
'writer's' becomes 's' (I can't explain this - if you can you should give a lot more credence to this answer).
'mark'+'s'='MARKS'
Can you help me to learn more?
(Other definitions for marks that I've seen before include "Former German currency" , "Grades assigned to school work" , "See 8" , "Visible impressions" , "Targets" .)