Lock up woman concerned with protecting elected member (8)
I believe the answer is:
imprison
'lock up' is the definition.
(I've seen this before)
'woman concerned with protecting elected member' is the wordplay.
'woman' becomes 'iris' (woman's name).
'concerned with' becomes 'on' (I've seen this in other clues).
'protecting' indicates putting letters inside (inserted letters are held or protected).
'elected member' becomes 'MP' (Member of Parliament).
'iris'+'on'='irison'
'irison' going around 'mp' is 'IMPRISON'.
(Other definitions for imprison that I've seen before include "Put away" , "Place in custody" , "Purveyor of blooms" , "Send down" , "Confine" .)