Several years ago, I heard someone claim that the distinction between "recession" and "depression" is less than 100 years old. Apparently all economic downturns used to be called a "recession." But when things began to head south in the 1930s, economists tried to assuage concerns by telling people that we're not really in a recession; it's just a mild depression and nothing to get alarmed over.
This, of course, backfired spectacularly as the "mild depression" turned into one of the greatest economic collapses in modern history, and nowadays the term refers, not to something that's kinda like a recession but milder, but something that's kinda like a recession but worse.
It's a very interesting story, but is it true? I tried to verify it but between articles on (medical) depression and articles on the events surrounding the Great Depression, the history of the term itself is annoyingly hard to Google!