One who stayed in bed (5)
I believe the answer is:
layer
'bed' is the definition.
(I know that bed can be written as layer)
I don't understand the remainder of the clue.
Can you help me to learn more?
(Other definitions for layer that I've seen before include "Hen, perhaps" , "Productive chicken" , "Thin sheet - productive hen" , "Single thickness, tier" , "Stratum; chicken" .)