Holy ground covered in East European event (7)
I believe the answer is:
episode
'event' is the definition.
(I've seen this before)
'holy ground covered in east european' is the wordplay.
'holy' becomes 'pi' (I've seen this in other clues).
'ground' becomes 'sod' (sod is a kind of ground**).
'covered in' says to put letters next to each other (some letters go on top of or cover others).
'east' becomes 'e' ('E' can be a synonym of 'east').
'european' becomes 'e' (abbreviation e.g. EU).
'pi'+'sod'='pisod'
'pisod' put after 'e' is 'episod'.
'episod'+'e'='EPISODE'
(Other definitions for episode that I've seen before include "Instalment; event" , "Event or series of events in a story" , "Story instalment" , "One part of a series" , "Instalment of a TV series" .)