Textile worker said to be dreadful (4)
I believe the answer is:
dire
'be dreadful' is the definition.
(synonyms)
'textile worker said' is the wordplay.
'textile worker' becomes 'dyer' (I've seen this in another clue).
'said' shows a homophone (sound like).
'dyer' is a homophone of 'DIRE'.
'to' acts as a link.
(Other definitions for dire that I've seen before include "Disastrous" , "Appalling or extreme" , "Ride around can be calamitous" , "Portentous" , "Ride off in dreadful way" .)