Secures a quick three points (7)
I believe the answer is:
fastens
'secures' is the definition.
('fasten' can be a synonym of 'secure')
'a quick three points' is the wordplay.
'a quick' becomes 'fast' (I've seen this before).
'three points' becomes 'ENS' (East, North and South are compass points).
'fast'+'ens'='FASTENS'
(Other definitions for fastens that I've seen before include "Attaches firmly" , "Fatness (anag.)" , "fixes" , "Bolts" .)