re ‧ fine AC /rɪˈfaɪn/ BrE AmE verb [transitive]
[ Word Family: noun : ↑ refinement , ↑ refinery ; verb : ↑ refine ; adjective : ↑ refined ≠ ↑ unrefined ]
1 . to improve a method, plan, system etc by gradually making slight changes to it:
Car makers are constantly refining their designs.
2 . to make a substance purer using an industrial process ⇨ refinery :
oil refining