Weapon made by millions, the last word in creative skill (8)
I believe the answer is:
armament
'weapon' is the definition.
(thesaurus)
'millions the last word in creative skill' is the wordplay.
'millions' becomes 'm' (abbreviation).
'the last word' becomes 'amen' (last word in a prayer).
'in' indicates putting letters inside.
'creative skill' becomes 'art' (I've seen this before).
'm'+'amen'='mamen'
'mamen' placed into 'art' is 'ARMAMENT'.
'made by' acts as a link.
(Other definitions for armament that I've seen before include "Weaponry" , "Equipping for war" , "Munitions" , "The providing of weapons" .)