Remove ages on top of engravings (5)
I believe the answer is:
erase
'remove' is the definition.
(thesaurus)
'ages on top of engravings' is the wordplay.
'ages' becomes 'eras' (I've seen this before).
'on top of' indicates taking the first letters (I've seen 'on top' mean this).
The first letter of 'engravings' is 'e'.
'eras'+'e'='ERASE'
(Other definitions for erase that I've seen before include "Destroy recording on audio or video tape" , "Remove recorded material" , "Efface" , "Rub out, cancel" , "Blot out" .)