This is the 7096th most frequent Spanish word.
fil
"Fil" is not a standard Spanish word; it may be a typo or an abbreviation.
Here, 'fil' evokes the visual image of a slender, elongated material, in this case made of silver.
El fil de plata brillaba bajo la luz.
The silver thread shone under the light.
The word 'fil' is used metaphorically here to describe the 'thread' or main topic of the conversation.
El fil de la conversación fue interesante.
The thread of the conversation was interesting.
In this context, 'fil' refers to a physical thread used for sewing or joining materials together.