Covering gossip about two mums (7)
I believe the answer is:
yashmak
'covering' is the definition.
(yashmak is a kind of covering)
'gossip about two mums' is the wordplay.
'two mums' can mean two substitutions for 'mum'.
'gossip' becomes 'yak'.
'about' is an insertion indicator.
'mum' becomes 'sh' (both can mean to be quiet).
'mum' becomes 'ma' (both can mean mother).
'sh'+'ma'='shma'
'yak' going around 'shma' is 'YASHMAK'.
(Other definitions for yashmak that I've seen before include "Veil worn by Muslim women in some countries" , "Muslim woman's veil" , "veil over features" , "Veil concealing face worn by Muslim women" , "modest assumption" .)