Mother takes on agent to update land survey (5)
I believe the answer is:
remap
'update land survey' is the definition.
I don't know anything about this answer so I can't judge whether this works.
'mother takes on agent' is the wordplay.
'mother' becomes 'ma' (ma can mean mother).
'takes on' means one lot of letters goes inside another (inserted letters are worn or taken on).
'agent' becomes 'rep' (short for representative).
'ma' placed within 'rep' is 'REMAP'.
'to' acts as a link.
Can you help me to learn more?
(Other definitions for remap that I've seen before include "Make new plans" , "(In computing) change the assignment of a function to a key" , "Plot again" , "Draw a plan again" , "chart again" .)