I wonder how many hours have been wasted altogether on people learning, and misunderstanding, which of more or less they should use?
At least for me personally, 'less' was what I always saw everywhere being used, and had used myself many times before I discovered that 'more' was a thing.
And when I discovered 'more', it took me maybe a minute to figure out that it's pretty much exactly like 'less', but that I didn't like it as much, and with everyone else seemingly agreeing on that, I didn't put any further thought to it.
cat -> from the obscure verb "catenate". A regular user would never, ever find the connection unless someone points it out. It should be "join" or "merge" or "unify" or something.
dd -> "data description". Really? It should be "blockcopy" or something.
grep -> "globally search a regular expression and print". Again, really? It should be "find" or "search".
ls, mv, cp, rm are kind of ok but in this day and age they should definitely be list, move, copy, remove by default (with aliases if need be). Heck, 99% of Unix commands are too short for their own sake.
cron -> "Chronos". Really?, third edition. It should be "scheduler" or something.
I mean, at this point we've all moved on and have memorized all these commands and parameters, but a lot of brain cells have died for no real benefit to humanity.
This is a word that perfectly describes exactly what cat does. Cat doesn't merge; that's ambiguous. Is a merge an interleaving? Sometimes yes. What does unify even mean in the sense of chaining data streams? Join? Close, but still unclear what it does. Does it operate on files? And what would happen to the already widely deployed join command that does something completely different?
Concatenate is a great word. Great words deserve to be used. I'm sorry that some of us haven't seen the crushing need to reduce our vocabulary to the double plus good amount of words in the newspeak lexicon.
What I'm not sorry about is that new users have to spend time to learn the system they're mucking around in before they can be useful with it. That's not a design flaw; that's a feature.
"concatenate" is a lot more known than "catenate". And I'm pretty sure that even "concatenate" is quite low in usage compared to a more common verb (or set of verbs) which could be used to describe what cat does ("show", "join", "merge", "unify", etc).
Anyway, I was mostly ranting since at this point both "concatenate" as a de-facto standard term and "cat" as a default UNIX tool will probably outlive me and most likely my descendants as well :)