He wrote satires fast (5)
I believe the answer is:
swift
'fast' is the definition.
(similar in meaning)
I don't understand the rest of the clue.
Can you help me to learn more?
(Other definitions for swift that I've seen before include "wit?" , "Fast-moving bird" , "Fast - novelist" , "Quick and rapid like a long-winged bird" , "Quick Irish satirist?" .)