Be way out about a point (5)
I believe the answer is:
exist
'be' is the definition.
('exist' can be a synonym of 'be')
'way out about a point' is the wordplay.
'way out' becomes 'exit' ('exit' can be a synonym of 'way out').
'about' is an insertion indicator.
'a point' becomes 's' (S is an example).
'exit' enclosing 's' is 'EXIST'.
(Other definitions for exist that I've seen before include "Have objective reality" , "Subsist" , "Get a life!" , "Scrape by" , "quick!" .)