Whole lot at assembly (5)
I believe the answer is:
total
'whole' is the definition.
(similar in meaning)
'lot at assembly' is the wordplay.
'assembly' indicates anagramming the letters.
'lot'+'at'='lotat'
'lotat' is an anagram of 'TOTAL'.
(Other definitions for total that I've seen before include "Complete sum" , "to give the final figure" , "Count" , "outright" , "Whole amount" .)