Put in a complaint about a careless porter (6)
I believe the answer is:
report
'put in a complaint' is the definition.
The definition and answer can be both related to communication as well as being singular nouns.
Maybe there's an association between them I don't understand?
'a careless porter' is the wordplay.
'a careless' indicates anagramming the letters.
'porter' is an anagram of 'REPORT'.
'about' is the link.
Can you help me to learn more?
(Other definitions for report that I've seen before include "Narrative given by porter" , "Gunfire noise; rumour" , "Sudden noise; account of progress" , "Complain about - account" , "Journalist's account - explosive noise" .)