Ordinal in chapel, even thicker (8)
I believe the answer is:
eleventh
'ordinal' is the definition.
(ordinal form of eleven)
'in chapel even thicker' is the wordplay.
'in' indicates the answer is hidden within the clue.
'ELEVENTH' can be found hidden inside 'chapel even thicker'.
(Other definitions for eleventh that I've seen before include "last man in?" , "Ordinal number" , "at such a late hour?" , "This hour offers the last chance" , "The hour to be saved at in the nick of time" .)