In Des Plaines, Illinois (corner of Oakton and Mount Prospect), there is a company called UOP. I’ve found their website, and while the website did answer our question as to what they are, it does not explain why they’re called UOP. They are apparently a joint partnership of Union Carbide and Allied Signal, which doesn’t lend any useful explanation. Does anyone know what, if anything, UOP stands for?
According to this site:
Universal Oil Products would seem to be the answer.