Seize cat if cones knocked over (10)
I believe the answer is:
confiscate
'seize' is the definition.
('confiscate' can be a synonym of 'seize')
'cat if cones knocked over' is the wordplay.
'knocked over' is an anagram indicator.
'cat'+'if'+'cones'='catifcones'
'catifcones' with letters rearranged gives 'CONFISCATE'.
(Other definitions for confiscate that I've seen before include "Take control of" , "Seize as penalty - facts on ice (anag)" , "Take away (property)" , "Impound" .)