Arrangement of names, some without order, all together (2,5)
I believe the answer is:
en masse
'all together' is the definition.
(I've seen this before)
'arrangement of names some without order' is the wordplay.
'arrangement of' indicates anagramming the letters.
'without' is a deletion indicator.
'order' becomes 'om' (order of merit).
'some' with 'om' taken away is 'se'.
'names' with letters rearranged gives 'enmas'.
'enmas'+'se'='EN MASSE'
(Other definitions for en masse that I've seen before include "In a group U altogether" , "All together as a group" , "Sees man (anag.)" , "Many as one" , "In force" .)