Youth of frugality (3)
I believe the answer is:
gal
'youth' is the definition.
The definition and answer can be both people as well as being singular nouns.
Maybe there's a link between them I don't understand?
'of frugality' is the wordplay.
'of' says the answer is hidden in the clue.
'GAL' is hidden within 'frugality'.
Can you help me to learn more?
(Other definitions for gal that I've seen before include "Broad" , "measure of acceleration?" , "Lady" , "Lass" , "miss" .)