I couldn't find a trademark with only the word "threads" [1]. There's "U Threads" [2] for example, but it has a disclaimer: "NO CLAIM IS MADE TO THE EXCLUSIVE RIGHT TO USE "THREADS" APART FROM THE MARK AS SHOWN".

[1] https://www.uspto.gov/trademarks/search

[2] https://tmsearch.uspto.gov/bin/showfield?f=doc&state=4802:za...