Gritty midnight shower, your first? (6)
I believe the answer is:
grainy
'gritty' is the definition.
(synonyms)
'midnight shower your first?' is the wordplay.
'midnight' becomes 'g' (the middle letter in 'night').
'shower' becomes 'rain' (rainfall).
'your first?' becomes 'y' (1st letter of 'your').
'g'+'rain'+'y'='GRAINY'
(Other definitions for grainy that I've seen before include "gravelly" , "Old still can be this" , "(Of photo) having low resolution" , "Gritty" , "Granular" .)