@coluber2001,
When I was younger I worked in a meat packing factory. One of the jobs was 'humping' taking the sides of beef off the wagon and putting them in the chilling room. There was a rail in the ceiling and tenter hooks hung off that.
It was the name of the hooks that we would hang the beef on.
It may well have been used in the textile industry as well, but it's definitely what we called the hooks in the meat industry.
Tenterhooks is an eggcorn, a word that is commonly mispronounced as in eggcorn for acorn.
A lot of people think they are tenderhooks, similarly people think of escape goat, bowl in a China shop and from the gecko.
Comedian Dave Gorman does a whole show on it. He's one of these interactive comedians who uses social media and power point a lot. I think the show in question might have been googlewhack.
Then again all his shows are a bit off the wall, ghe first one was him tracking down 100 other people who were also called Dave Gorman.