Suspended hammers used upon about fifty (9)
I believe the answer is:
pendulous
'suspended' is the definition.
(I've seen this before)
'hammers used upon about fifty' is the wordplay.
'hammers' indicates anagramming the letters (I've seen 'hammering' mean this).
'about' means one lot of letters goes inside another.
'fifty' becomes 'L' (Roman numeral).
'used'+'upon'='usedupon'
'usedupon' anagrammed gives 'penduous'.
'penduous' enclosing 'l' is 'PENDULOUS'.
(Other definitions for pendulous that I've seen before include "Suspended" , "Drooping" , "Hanging loosely" , "hanging heavy" , "Dangling" .)