Shortage of thread (6)
I believe the answer is:
dearth
'shortage' is the definition.
(dearth can mean a shortage or lack)
'of thread' is the wordplay.
'of' indicates anagramming the letters (the answer comes from or 'of' the letters).
'thread' anagrammed gives 'DEARTH'.
(Other definitions for dearth that I've seen before include "deficiency" , "Insufficient amount" , "Red hat for scarcity" , "Hatred (anag) -- shortage" , "Severe lack" .)