Trade working hours in shortage (6)
I believe the answer is:
dearth
'shortage' is the definition.
(dearth can mean a shortage or lack)
'trade working hours' is the wordplay.
'working' indicates anagramming the letters.
'hours' becomes 'h'.
'trade' with letters rearranged gives 'deart'.
'deart'+'h'='DEARTH'
'in' acts as a link.
(Other definitions for dearth that I've seen before include "From shortage of food" , "Scarcity - lack" , "Scarcity of thread" , "Severe shortage" , "poverty" .)