Consensus on language tends to lag behind behaviors. We do things first, and then we figure out ways to describe them. Plenty of technology companies have noticed this pattern and tried to game it. It's why you hear a brand like Bing trying to encourage use of its name as a verb, the way we talk about googling, xeroxing and instagramming. Microsoft even paid for “Bing it” dialogue in episodes of Gossip Girl. But most of the language we use to describe technology evolves from the ground up.

"Terms that relate to communication technology may start off as being rather technical and obscure," Zimmer said. "They become mainstream because people need a term to refer to the things we're doing, so they get clipped or shortened to various diminutive forms."

Before email, we had "electronic mail," which was also the term used to describe faxes in their early days. "Moving pictures" turned into "motion pictures" and "movies." (And a word of caution to those who keep declaring "peak selfie:" In 1925, The New York Times decided "the moving picture is now at the zenith of its power.") Early coverage of the television refers to "visual broadcasts," "broadcast pictures," and "radio sight." As time goes on, we find ways to simplify clunkier and more descriptive terms.

"You can't really dictate these things," Zimmer said. "There can be a lot of flux early-on, a lot of competing usage. But when people have already fixed on one particular term, it's hard to displace it with something else. And so that's why we sometimes get older or more anachronistic terms sticking around. Then you have the conservative forces of language, which serve to create a sort of inertia around those terms until the next wave."

This helps explain what’s happening with “selfie” because the word has been established, even as the thing itself continues to evolve.

Selfies tell dramatic stories:

They serve as visual trail-markers:

Even the photos that clearly aren’t self-taken but evoke selfies compositionally are called selfies, like the close-up shots of animals in this BuzzFeed list of selfies, for example. And as selfies become more culturally ingrained, we’ve also seen more photographs of selfies — images that reveal the moment of the selfie as it’s being taken, but not the photographic result. (See: Photos of selfies of Meryl Streep and Hillary Clinton, Bill de Blasio and the New York City press corps, etc.)

Is it still a selfie if you use a selfie stick to hold the camera farther away than at arm's length?

"I feel that the selfie definition would insist on you holding the camera and you being in the photo, but it could also accommodate others," said Ben Yagoda, a journalism professor at the University of Delaware who has written several books about language.