Noise mostly almost shattered still (10)
I believe the answer is:
motionless
'still' is the definition.
('motionless' can be a synonym of 'still')
'noise mostly almost shattered' is the wordplay.
'almost' means to remove the last letter (most of the word but not all of it).
'shattered' indicates anagramming the letters.
'noise'+'mostly'='noisemostly'
'noisemostly' with its final letter taken away is 'noisemostl'.
'noisemostl' with letters rearranged gives 'MOTIONLESS'.
(Other definitions for motionless that I've seen before include "constipated?" , "not having anything to vote about?" , "Inert" , "Still, unmoving" , "Static" .)