Try blocking extremely spurious cuts (6)
I believe the answer is:
shears
'cuts' is the definition.
(shearing is a kind of cutting)
'try blocking extremely spurious' is the wordplay.
'try' becomes 'hear' (as in to try someone in court or hear their case**).
'blocking' is an insertion indicator.
'extremely' says to hollow out the word (remove centre letters).
'spurious' with its centre taken out is 'ss'.
'hear' inserted into 'ss' is 'SHEARS'.
(Other definitions for shears that I've seen before include "Pruners" , "Large clippers" , "Cuts the fleece of sheep" , "fractures under pressure" , "Garden cutting implement" .)