Row involving one oddly like a big cat (7)
I believe the answer is:
leonine
'like a big cat' is the definition.
(leonine means like a lion)
'row involving one oddly' is the wordplay.
'row' becomes 'line' (as in a row of things).
'involving' means one lot of letters goes inside another.
'oddly' is an anagram indicator.
'one' is an anagram of 'eon'.
'line' going around 'eon' is 'LEONINE'.
(Other definitions for leonine that I've seen before include "like one with largest share" , "As a maned animal" , "Descriptive of pride" , "Unusually courageous" , "Resembling lions" .)