Big cat making rosella sporadically soar? (3)
I believe the answer is:
leo
'big cat' is the definition.
'leo' can be an answer for 'cat' ('lion' in Latin). I'm unsure of the 'big' bit.
I can't explain the remainder of the clue.
Can you help me to learn more?
(Other definitions for leo that I've seen before include "Pope" , "Zodiacal lion" , "Star sign of one born on August 1" , "sign of summer" , "Horoscope sign" .)