Be quiet about mother's financial failure (5)
I believe the answer is:
smash
'financial failure' is the definition.
'smash' can be an answer for 'failure' (thesaurus). I am unsure of the 'financial' bit.
'be quiet about mother's' is the wordplay.
'be quiet' becomes 'sh' (both are said to tell someone to stop speaking).
'about' is an insertion indicator.
'mother's' becomes 'ma's' (ma can mean mother).
'sh' placed around 'mas' is 'SMASH'.
Can you help me to learn more?
(Other definitions for smash that I've seen before include "Break like a glass or cup" , "Break completely" , "something very popular" , "Wreck" , "defeat" .)