Take in case of broken limb being blue (8)
I believe the answer is:
downcast
'being blue' is the definition.
(I've seen this before)
'take in case of broken limb' is the wordplay.
'take in' becomes 'down' (downing is a kind of taking in).
'case of broken limb' becomes 'cast' (I can't justify this - if you can you should give a lot more credence to this answer).
'down'+'cast'='DOWNCAST'
Can you help me to learn more?
(Other definitions for downcast that I've seen before include "Dispirited, gloomy" , "Sad" , "disheartened" , "Crestfallen" , "Depressed - looking at the floor?" .)