Eagle circling round one man (5)
I believe the answer is:
ernie
'man' is the definition.
(I've seen this before)
'eagle circling round one' is the wordplay.
'eagle' becomes 'erne' (erne is a kind of eagle).
'circling' means one lot of letters goes inside another (circling can mean going around or containing).
'round one' becomes 'i' (Roman numeral. I am not sure about the 'round' bit.).
'erne' going around 'i' is 'ERNIE'.
Can you help me to learn more?
(Other definitions for ernie that I've seen before include "National Savings computer" , "Premium?bond computer" , "Premium Bonds selector" , "--- Wise, comedian" , "One regularly drawing" .)