Gaff about Andrew's first royal residence (6)
I believe the answer is:
palace
'royal residence' is the definition.
(I've seen this before)
I don't understand the rest of the clue.
Can you help me to learn more?
(Other definitions for palace that I've seen before include "Locality round a monarch's official residence" , "Regal mansion" , "See 23" , "Grand building" , "Official residence of a sovereign" .)