UK map changed with English constitution (4-2)
I believe the answer is:
make-up
'constitution' is the definition.
(I've seen this before)
'uk map changed with english' is the wordplay.
'changed with' indicates an anagram.
'english' becomes 'e' (abbreviation).
'uk'+'map'='ukmap'
'ukmap' anagrammed with 'e' gives 'MAKE-UP'.
(Other definitions for make-up that I've seen before include "foundation?" , "Cosmetics, face-paint" , "Cosmetics applied to face" , "Facial cosmetics" , "Lipstick, mascara etc" .)