Everybody in associations counts (7)
I believe the answer is:
tallies
'counts' is the definition.
('tally' can be a synonym of 'count')
'everybody in associations' is the wordplay.
'everybody' becomes 'all' (I've seen this before).
'in' means one lot of letters goes inside another.
'associations' becomes 'ties' ('tie' can be a synonym of 'association').
'all' placed within 'ties' is 'TALLIES'.
(Other definitions for tallies that I've seen before include "Counts, of votes say" , "Matches, corresponds" , "Reckons debt or score" , "Recordings" , "Sums up" .)