Mother crossing heart now and then for revered leader (7)
I believe the answer is:
mahatma
'revered leader' is the definition.
The definition and answer can be both people as well as being singular nouns.
Perhaps there's a link between them I don't understand?
'mother crossing heart now and then' is the wordplay.
'mother' becomes 'mama' (mama informally means mother).
'crossing' is an insertion indicator.
'now and then' indicates alternate letters (letters taken on a regular basis, now and then).
The alternating letters of 'heart' are 'hat'.
'mama' enclosing 'hat' is 'MAHATMA'.
'for' acts as a link.
Can you help me to learn more?
(Other definitions for mahatma that I've seen before include "(Indian) holy person or sage" , "Gandhi's title" , "Wise and holy leader in 12" , "Gandhi, for example" , "Holy man" .)