One found in bed happened to have a bad back (8)
I believe the answer is:
camellia
'one found in bed' is the definition.
Although both the answer and definition are singular nouns, I cannot see how they can define each other.
'happened to have a bad back' is the wordplay.
'happened' becomes 'came' (coming is a kind of happening).
'to have' says to put letters next to each other.
'bad' becomes 'ill' (similar in meaning).
'back' shows that the letters should be reversed in order.
'a'+'ill'='aill'
'aill' back-to-front is 'llia'.
'came'+'llia'='CAMELLIA'
Can you help me to learn more?
(Other definitions for camellia that I've seen before include "Email Cal about the flowering shrub" , "10" , "Ornamental shrub with rose-like flowers" , "Showy shrub, rel. to tea" , "Shrub related to tea plant" .)