Support available in lost employment (4)
I believe the answer is:
stem
'support' is the definition.
(I've seen this before)
'available in lost employment' is the wordplay.
'available in' indicates a hidden word.
'STEM' can be found hidden inside 'lost employment'.
(Other definitions for stem that I've seen before include "something growing?" , "Originate (from)" , "Slender upright part, of flower or glass" , "Axis" , "Dam" .)