Maiden of frugality (3)
I believe the answer is:
gal
'maiden' is the definition.
(thesaurus)
'of frugality' is the wordplay.
'of' indicates the answer is hidden within the clue.
'GAL' is hidden in the letters of 'frugality'.
(Other definitions for gal that I've seen before include "Girl from American west" , "An American girl, cowboy vintage" , "miss" , "US female" , "measure of acceleration?" .)