Figure out, only about five (5)
I believe the answer is:
solve
'figure out' is the definition.
('solve' can be a synonym of 'figure out')
'only about five' is the wordplay.
'only' becomes 'sole' ('sole' can be a synonym of 'only').
'about' is an insertion indicator.
'five' becomes 'v' (roman numeral).
'sole' enclosing 'v' is 'SOLVE'.
(Other definitions for solve that I've seen before include "Get the answers" , "Complete crossword" , "Find the answer to a mystery" , "Explain (a mystery)" , "Deal with (a problem)" .)