Like workhorses (4)
I believe the answer is:
shod
'like workhorses' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for shod that I've seen before include "(Of a horse) with shoes on" , "Wearing shoes" , "Fitted with footwear" , "Fitted with horseshoes" , "Not with bare feet" .)