Beatle widow ducks around North Head (3)
I believe the answer is:
ono
'beatle widow' is the definition.
I don't know anything about this answer so I can't judge whether it can be defined by this definition.
'ducks around north head' is the wordplay.
'ducks' becomes 'oo' (two O's - duck means zero in cricket).
'around' is an insertion indicator.
'head' indicates taking the first letters.
The initial letter of 'north' is 'n'.
'oo' placed around 'n' is 'ONO'.
Can you help me to learn more?
(Other definitions for ono that I've seen before include "Or nearest offer (abbr.)" , "Yoko ..., wife of John Lennon" , "Singer's wife" .)