Very heavy spades wielded by old worker (5)
I believe the answer is:
obese
'very heavy' is the definition.
(I've seen this in another clue)
'spades wielded by old worker' is the wordplay.
I cannot quite see how this works, but
'spades' could be 's' (abbreviation in card games) and 's' is present in the answer.
'old' could be 'o' (common abbreviation eg in OE for Old English) and 'o' is found within the answer.
'worker' could be 'bee' (a worker bee) and 'bee' is present in the remaining letters.
This accounts for all the letters.
This may be the basis of the clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for obese that I've seen before include "Enormous" , "round" , "Unusually fat" , "Much too fat" , "Grossly fat" .)