End of chapel and end of church showing gap (5)
I believe the answer is:
lapse
'gap' is the definition.
(thesaurus)
'end of chapel and end of church' is the wordplay.
'end of' indicates one should take the final letters.
'and' is a charade indicator (letters next to each other).
'end of church' becomes 'apse' (I've seen this in another clue).
The final letter of 'chapel' is 'l'.
'l'+'apse'='LAPSE'
'showing' is the link.
(Other definitions for lapse that I've seen before include "Fall back" , "Fault" , "Brief failure of judgement" , "Sepal (anag)" , "A slight error or a passage of time" .)