Sandy area around central Greenwich (5)
I believe the answer is:
arena
'sandy area around central greenwich' is the definition.
I can't judge whether this definition defines the answer.
'area around central greenwich' is the wordplay.
'around' means one lot of letters goes inside another.
'central' says to take the centre.
The middle of 'greenwich' is 'n'.
'area' placed around 'n' is 'ARENA'.
Can you help me to learn more?
(Other definitions for arena that I've seen before include "Scene of open conflict" , "Where gladiators fought" , "Sit around here being entertained" , "Place of great activity" , "theatre" .)