What's a millionaire?

This seems like an easy question, but it isn't. We tend to think of millionaires the way we think of Scrooge McDuck: They've got some big storehouse of cash somewhere or something, apparently? Like, we know they don't literally have a million dollars in gold coins they swim through, but they have a million in the bank? Or I guess they may also have stocks that add up to a million. Do houses count? Does having a million-dollar house make you a millionaire?

It's not necessarily as clear as it seems, but that usually doesn't matter. We generally mean "millionaire" to mean "rich," even though, thanks to inflation, a million dollars isn't what it used to be. If you had a million dollars in 1916, that would be worth $21.7 million today. Or, working the other direction, having a million bucks in 2016 is like having $46,000 a century ago. Between 1900 and 1925, the word "millionaire" appeared in the New York Times 6,621, while the word "billionaire" only appeared 187 times. Between 1990 and 2015, "millionaire" appeared 7,221 -- and "billionaire" appeared 15,327 times.

But the conflation of "millionaire" and "rich" does matter in a political context. After all, Bernie Sanders has spent months railing against the top one percent, which is to say "wealthy people" which is to say "millionaires and billionaires."

On Tuesday morning, Money magazine published an article that seems to poke a hole in Sanders's objections to America's wealthy: He, too, is a de facto millionaire! Hypocrisy!

Obviously "de facto" does a lot of work in that sentence. What's a de facto millionaire? Well, according to Money's analysis, Sanders's congressional pension would cost $1 million if someone else his age suddenly decided he wanted to have something similar. Plus, his retirement plan is probably worth about $700,000? Plus his wife, Jane, has her own retirement plan. All total, Money estimates that the couple's "retirement nest egg" could be worth $2 million. Ergo, de facto.

If "having retirement plans worth a million dollars" doesn't exactly strike you as equivalent to "being a millionaire," you are probably not alone. It's true that the nest egg offers Sanders more long-term security than other Americans, just as it is likely true that the value of that nest egg is in the seven figures. But it's hard to see that as meaning that Bernie Sanders himself is a millionaire.

In fact, the mathematical gymnastics needed to add up Sanders's wealth to more than $1,000,000 helps highlight the contrast between the Sanderses of the world and the people who his campaign has targeted. As we noted earlier this year, many major corporate CEOs have likely earned more than a million dollars in salary already this year. GE's Jeffrey Immelt, for example, has made about $2.3 million since Jan. 1, assuming he's paid evenly at the salary reported by Payscale. That's a different level from a guy who might have $2 million in retirement savings and guaranteed income.

Sanders means the hedge fund managers, the 25-best-paid of whom took home more in compensation in 2014 than every kindergarten teacher in America was paid in 2012. That's a millionaire.

That vagueness works against Sanders, too. His excoriation of millionaires and billionaires is an excoriation of a poorly defined group of people into which a lot of folks might fit. Average annual income in the United States was $53,657 in 2014, but that doesn't include houses and stocks and things like retirement plans. The boundaries of who is and isn't a millionaire are vague.

We understand Sanders's point though. He doesn't mean de facto millionaires, even if he weren't one. "Millionaire" by itself, weirdly enough, no longer necessarily means "rich."

This article has been updated to clarify that it was Money magazine, not Time, that published the article.