Treated as canards — her prophecies were! (9)
I believe the answer is:
cassandra
But I can't explain it at all! Could you help me understand?
(Other definitions for cassandra that I've seen before include "whose predictions nobody believed?" , "one having gloomy views" , "forecaster" , "Prophetess during the Trojan War whose predictions were true but never believed" , "Prophesying daughter of Priam of Troy" .)