Border commitment having no place (4)
I believe the answer is:
edge
'border' is the definition.
(I know that edge is a type of border)
'commitment having no place' is the wordplay.
'commitment' becomes 'pledge' (pledge is a kind of commitment).
'having no' indicates named letters should be taken away.
'place' becomes 'pl' (abbreviation used in postal addresses).
'pledge' with 'pl' taken out is 'EDGE'.
(Other definitions for edge that I've seen before include "Rim or slight advantage" , "Perimeter" , "Margin, outside limit" , "Border - meeting place" , "Move little by little to the border" .)