Honest woman twice left out (5)
I believe the answer is:
level
'honest' is the definition.
(level can mean fair or honest)
'woman twice left out' is the wordplay.
'woman' becomes 'eve' (Eve is an example).
'twice' says to double the letters.
'left' becomes 'l' (common abbreviation).
'out' indicates putting letters inside.
'l' duplicated is 'll'.
'eve' inserted inside 'll' is 'LEVEL'.
(Other definitions for level that I've seen before include "Horizontal line" , "Even - equal" , "Flatten" , "Palindromically smooth" , "Standard" .)