Before Synthetics, Used to String Tennis Rackets
Puzzle 11 of Halloween Movies Medium Pack
Question is: Before Synthetics, Used to String Tennis Rackets
and the answer is: CATGUT
Word Meaning:
CATGUT — (countable) A cord of great toughness made from the intestines of animals, especially of sheep, used for strings of musical instruments, racquets, sutures etc.
Definitions from Wiktionary.