The adjective flyblown has 3 meanings:
Meaning #1: spoiled and covered with eggs and larvae of flies
Synonym: maggoty
Meaning #2: foul and run-down and repulsive
Synonyms: squalid, sordid
Meaning #3: especially of reputation
Synonyms: besmirched, damaged, spotted, stained, sullied, tainted, tarnished
Meaning #4: having been pleasured by a member of the species Musca domestica