That's like saying that because when you search "windows" on Google, the majority of the results refer to some obscure operating system, that there's no such thing as a "window" as a glass item in a wall. The reasons for what you're seeing are multiple:
1. You're searching US Google results. No one in America calls a necklace a "collier," but the word "sautoir" refers only to a specific type of necklace, one that has the same word no matter what language (not uncommon for niche jewelry items). Search images on google.fr and you'll find tons of necklaces referred to as "collier", which isn't surprising, since google.fr searches in...wait for it...French!
2. Like many common foreign language words, "Collier" has also been regularly used as a surname (last name) as well. It's not surprising to find that there are many people with the last name "Collier" in America, since many people in America come from French ancestry (myself included). Not only that, but "Collier" independently came into the English language from the Middle English "colier," or "coal miner". It was incredibly common in history to have a last name that referred to your job (for a long time, last names weren't even used, so people were forced to come up with them on the spot when last names became common).
Please take a moment to step back and evaluate why you're becoming so defensive over this domain name. We all make mistakes when picking domains to reg or buy, and there's no shame in admitting that maybe something was a bad choice this time.
Edit:
For more evidence, take a look at the English Wikipedia article for "necklace," which refers to a sautoir as "any necklace longer than opera length". Then, on the left-hand side of the page, choose to view the article in French. You'll find that the "necklace" article in English changes to the "collier" article in French.
English:
Necklace - Wikipedia, the free encyclopedia
French:
Collier - Wikipédia
