Ungrateful daughter throttling a former president (6)
I believe the answer is:
reagan
'former president' is the definition.
(I've seen this before)
'ungrateful daughter throttling a' is the wordplay.
'ungrateful daughter' becomes 'regan' (I've seen this before).
'throttling' means one lot of letters goes inside another.
'regan' placed around 'a' is 'REAGAN'.
(Other definitions for reagan that I've seen before include "40th president of the United States" , "Former leader" , "US president, 1981-89" , "leading actor, once?" , "head of state" .)