Gossip involves terrible sham means of covering up (7)
I believe the answer is:
yashmak
'of covering up' is the definition.
I can't tell whether this defines the answer.
'gossip involves terrible sham' is the wordplay.
'gossip' becomes 'yak'.
'involves' is an insertion indicator.
'terrible' is an anagram indicator.
'sham' anagrammed gives 'shma'.
'yak' going around 'shma' is 'YASHMAK'.
'means' is the link.
Can you help me to learn more?
(Other definitions for yashmak that I've seen before include "Muslim woman's veil" , "Face-veil for Muslim women like shaky ma" , "Veil concealing face worn by Muslim women" , "Facial veil" , "Face covering" .)