Family members left in ceramic oven (4)
I believe the answer is:
kiln
'ceramic oven' is the definition.
(I've seen this in another clue)
'family members left in' is the wordplay.
'family members' becomes 'kin' (I've seen this before).
'left' becomes 'L' (common abbreviation).
'in' is an insertion indicator.
'kin' enclosing 'l' is 'KILN'.
(Other definitions for kiln that I've seen before include "Large oven for baking pottery" , "Drying furnace" , "Furnace, oven" , "Potter's Friend" , "Potter's furnace" .)