Note about one oddly like a big cat (7)
I believe the answer is:
leonine
'like a big cat' is the definition.
(I've seen this in another clue)
'note about one oddly' is the wordplay.
'note' becomes 'line' (synonyms).
'about' means one lot of letters goes inside another.
'oddly' indicates anagramming the letters.
'one' anagrammed gives 'eon'.
'line' going around 'eon' is 'LEONINE'.
(Other definitions for leonine that I've seen before include "Resembling a lion" , "Like the king of the beasts" , "Beastly" , "like one with largest share" , "Resembling a big cat" .)