When circling, wild monster is concerning (2,5,2)

'is concerning' is the definition.
(I've seen this in another clue)

'when circling wild monster' is the wordplay.
'when' becomes 'if'.
'circling' means one lot of letters goes inside another (circling can mean going around or containing).
'wild' indicates anagramming the letters.
'monster' is an anagram of 'ntermso'.
'if' going around 'ntermso' is 'IN TERMS OF'.