Fi : interj. (onomatopoeia, word coming from the radical of the Latin fimus « manure ").
The word “fi” has several meanings:
1. Aged or pleasant meaning: Interjection expressing disapproval, disdain, contempt, disgust (Ugh).
Quotation from the French writer Stendhal (1783-1842): “Fi So! she said, pushing him away.
2. Verbal expression: doing fide: to disdain, despise.
He does fiend my advices.