I have never heard someone use the word “rube” in my life. At first glance, I thought it was related to rubiks cube or a ruby gem. But a quick search on the internet showed me it’s a negative word to describe an unsophisticated person who is from a rural area. A synonym is hick or bumpkin.
If you ever want to insult someone indirectly, the word to use would be “rube.” They may call you a “rube” back. It’ll sound like the most sophisticated yet incomprehensible verbal insult to bystanders.
Overall, the words posted on the daily prompts are definitely exposing me dig deeper into the meaning of words and to learn some esoteric ones along the way: rube is one of them.