Calls by six minds (6)
I believe the answer is:
visits
'calls' is the definition.
(I know this)
'by six minds' is the wordplay.
'by' says to put letters next to each other.
'six' becomes 'VI' (Roman numerals).
'minds' becomes 'sits' (I can't explain this - if you can you should believe this answer much more).
'vi' next to 'sits' is 'VISITS'.
Can you help me to learn more?
(Other definitions for visits that I've seen before include "Pays a call" , "Comes by, drops in" , "Call to see" , "Social calls" , "Calls in to see" .)