Unspecified amount or number (4)
I believe the answer is:
some
I believe this clue is a double definition.
'unspecified amount' is the first definition.
(I've seen this in another clue)
'number' is the second definition.
(I have seen 'Undefined number ' mean 'some' so perhaps 'number' could also mean 'some')
(Other definitions for some that I've seen before include "Undefined number" , "An unspecified quantity, not all" , "Part" , "Hard work" , "Unknown or unspecified amount or number" .)