Subsist on a meagre allowance (6)
I believe the answer is:
scrimp
'subsist on a meagre allowance' is the definition.
(I've seen this before)
This is all the clue.
(Other definitions for scrimp that I've seen before include "Do or spend less than is needed" , "Be thrifty and parsimonious" , "Be economical, mean, with" , "Watch the pennies" , "Pinch and save" .)