Exact word for the material which is used to thread Tennis racquets

Solution 1:

Tennis String

The material used for a long time to string a Tennis racket (racquet is use more in club names than in daily use) is Catgut

Natural gut is still used as a high-performance string in tennis racquets, although it had more popularity in the past and is being displaced by synthetic strings.

Fishing Line

For fishing lines, the materials are more diverse

Modern fishing lines intended for spinning, spin cast, or bait casting reels are almost entirely made from artificial substances, including nylon, polyvinylidene fluoride (PVDF, and called fluorocarbon), polyethylene, Dacron and Dyneema (UHMWPE). The most common type is monofilament, made of a single strand.

RE Racket vs Racquet:

At www.wilson.com/en-us/ and www.wilson.com/en-gb/ the word is racket however they sell Wilson racquets AND rackets at amazon

Amazon.com:

Amazon.co.uk: