What covers stone over old man? (7)
I believe the answer is:
epitaph
'man?' is the definition.
Although both the answer and definition are singular nouns, I can't see how one could define the other.
'what covers stone over old' is the wordplay.
'what' becomes 'eh' (sound used to ask 'what?' or 'pardon?').
'covers' indicates putting letters inside.
'stone' becomes 'pit' (synonyms).
'over old' becomes 'ap' (I can't explain this - if you can you should believe this answer much more).
'pit'+'ap'='pitap'
'eh' enclosing 'pitap' is 'EPITAPH'.
Can you help me to learn more?
(Other definitions for epitaph that I've seen before include "message about late departure" , "Gravestone inscription" , "Words written on a gravestone" , "last words" , "Words carved on a gravestone" .)