Cover perhaps over mum in Hong Kong (7)
I believe the answer is:
yashmak
'cover' is the definition.
(I've seen this before)
'perhaps over mum in hong kong' is the wordplay.
'perhaps' becomes 'say' (both can mean 'for example').
'over' is a reversal indicator.
'mum' becomes 'ma' (ma can mean mother).
'in' is an insertion indicator.
'hong kong' becomes 'HK' (abbreviation for Hong Kong).
'say' in reverse letter order is 'yas'.
'ma' going into 'hk' is 'hmak'.
'yas'+'hmak'='YASHMAK'
(Other definitions for yashmak that I've seen before include "Moslem woman's double veil" , "Veil worn in public by Muslim women" , "Veil worn by Muslim women in some countries" , "Muslim woman's veil" , "Face-veil worn by Muslim women" .)