What does "uber-word" mean in particular context (see body of question)?
Solution 1:
I don't think it is possible to know exactly what the commentator meant without asking him or her, but there are several possibilities. An uber-word could be:
- a superlative word (which was how I initially understood it)
- a trendy word (that pushes out the native one for a while)
- a "cuckoo" word that usurps all native words
It's this last one that I'm leaning towards at the moment, as this is how the taxi firm operates, and this is the most well known use of the word uber at the moment.
Solution 2:
According to Wiktionary, it means "Super; high-level; high-ranking". I believe "uber" or "über" has become synonym of "super", as Wikipedia explains:
"One of the first popular modern uses of the word as a synonym in English for super was a Saturday Night Live TV sketch in 1979. The sketch, What if?, pondered the notion of what if the comic book hero Superman had landed in Nazi Germany when he first came from Krypton. Rather than being called Superman, he took the name of Übermann."
There are some interesting definitions and theories on the origin of "uber" in Urban Dictionary, but no authoritative sources to back them up. In any case, they also tend to support the idea that "uber" is used as a synonym of "super," even in the context you give.
Solution 3:
In a comment, John Lawler answered:
Uber- is a new libfix in American English at any rate. It comes from German über, meaning ‘over’, which came into English as das Übermensch ‘Superman’ from Nietzsche's writings.
English doesn't have the right vowels to say über, especially capitalized, but the recent advent of the ride-sharing Uber company has made it more popular [spelled with] with /u/ instead of /ü/.
In this sense uber means ‘popular, famous, stylish, important’.