Big chap who was catapulted to fame (7)
I believe the answer is:
goliath
'big chap' is the definition.
The definition and answer can be both people as well as being singular nouns.
I also know that 'big' relates to this answer.
I can't explain the rest of the clue.
Can you help me to learn more?
(Other definitions for goliath that I've seen before include "Giant Philistine flattened by David" , "David slew him with a slingshot (7)" , "Giant Philistine killed by David" , "Giant Philistine felled by David" , "Giant David slew" .)