That's actually a good name
Ring.
Amazon.
The irony is that a google search for Vector first comes up with Vector Marketing, which sells Cutco Knives.
God I remember that shitty company. They recruit University students to sell their knives to their friends and family. They're not really good knives either, just slightly better than most store knives and sold at a markup near that of really high end commercial knives.
If you founded you company in the 1980's for sure you can choose any good sounding name, even a very common fruit and it willl be alright.
But in 2020 please don't hurt the community of devellopers that deal with graphical element by reverting to such a generic random name...
Even if the Deciders called it Vector.im or Vector Messenger, and did some SEO, it wouldn't be that hard to find.
In fact Riot.im shows up at #8 on DDG and #6 on Google (for me) when "riot" is searched, even when "riot" is a very hyped up search term. (https://trends.google.com/trends/explore?q=riot)
Agreed it's not the best parallel to draw these days, though...