Record list of many deer (5)
I believe the answer is:
chart
'record list' is the definition.
The definition and answer can be both related to communication as well as being singular nouns.
Maybe they are linked in a way I don't understand?
'many deer' is the wordplay.
'many' becomes 'c' (C is the Roman numeral for 100).
'deer' becomes 'hart' (hart is a kind of deer).
'c'+'hart'='CHART'
'of' is the link.
Can you help me to learn more?
(Other definitions for chart that I've seen before include "[LOVE ME DO] became the first of many to ..." , "series of plots?" , "Plan" , "Marine map" , "Hit parade" .)