Mostly pack rupees after liquidating capital (5,4)
I believe the answer is:
upper case
'capital' is the definition.
(I know that capital can be written as Upper case)
'mostly pack rupees after liquidating' is the wordplay.
'mostly' means to remove the last letter.
'after liquidating' indicates an anagram (letters become liquid or fluid).
'pack' with its final letter removed is 'pac'.
'pac'+'rupees'='pacrupees'
'pacrupees' anagrammed gives 'UPPER-CASE'.
(Other definitions for upper case that I've seen before include "LSD, but not pot, is in this" , "used to begin sentence" , "Where caps found" , "characters starting sentences?" , "Description of letters like THESE" .)