Deign to climb down after deception (10)
I believe the answer is:
condescend
'deign' is the definition.
('condescend' can be a synonym of 'deign')
'climb down after deception' is the wordplay.
'climb down' becomes 'descend' (I've seen this before).
'after' means one lot of letters go next to another.
'deception' becomes 'con' (I've seen this before).
'descend' put after 'con' is 'CONDESCEND'.
'to' is the link.
(Other definitions for condescend that I've seen before include "one does this as a favour?" , "Show that one feels superior" , "See fit" , "Do something below one's dignity" , "Deign" .)