The whole firm, with request for help, will receive millions (6)
I believe the answer is:
cosmos
'the whole' is the definition.
(I've seen this before)
'firm with request for help will receive millions' is the wordplay.
'firm' becomes 'co' (abbreviation for company).
'with' says to put letters next to each other.
'request for help' becomes 'sos' (I've seen this in another clue).
'will receive' indicates putting letters inside.
'millions' becomes 'm' (abbreviation).
'sos' placed around 'm' is 'smos'.
'co'+'smos'='COSMOS'
(Other definitions for cosmos that I've seen before include "Everything that exists" , "Universe seen as a whole" , "The universe - a daisy" , "Universe as an ordered whole" , "Universe as an ordered system" .)