Your crony is standing a round (3)
I believe the answer is:
pal
'your crony' is the definition.
I can't judge whether this defines the answer.
'standing a round' is the wordplay.
'standing' says the letters should be written in reverse.
'a round' becomes 'lap' (as in a round or lap of a park).
'lap' written backwards gives 'PAL'.
'is' acts as a link.
Can you help me to learn more?
(Other definitions for pal that I've seen before include "Buddy, chum" , "Mate, informal friend" , "Brother" , "Friend (colloq.)" , "Crony" .)