n, pl  -las  or  -lae   1  :  an abnormal passage leading from an abscess or hollow organ to the body surface or from one hollow organ to another and permitting passage of fluids or secretions <prepared a to obtain gastric juice from the dog>   2  :  FISTULOUS WITHERS
  - see CASSIA FISTULA  .
 
 Brit also   
 
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