By Josh Zeitlin, Senior Editor

It's been a busy few days in the industry. CMS canceled mandatory bundled payment models. The Senate passed a tax bill. CVS announced plans to buy Aetna.

And on Monday, the Associated Press reignited a debate that has divided clinicians, policymakers, and journalists alike, albeit one with few implications for patients' wellbeing: Should the phrase so often used to describe our industry be "healthcare"—one word—or "health care"?

That controversy bubbles up on Twitter every so often, but it really took off on Monday following AP's response to a Twitter question.

Several researchers and journalists were not pleased that AP would even consider changing its style (which many news publications follow) to "healthcare"—leading to many all-caps expressions of dismay.

"ANARCHY," said Politico's Jennifer Haberkorn. "MADNESS," said Axios' Sam Baker. "OH MY GOD NO," said The Incidental Economist Managing Editor Adrianna McIntyre.

Other lower-case responses were just as passionate. Loren Adler, associate director of the USC-Brookings Schaeffer Initiative for Health Policy, said, "It's two words. This shouldn't be a debate." Baker asked, "What building do i need to chain myself to in order to stop this?" Martin Gaynor, a professor of economics at Carnegie Mellon University, added, "To heck with the AP - never will my fingers omit a space between health and care!"

Not everyone was team "health care," however. Modern Healthcare's Erica Teichert in response to one of Baker's tweets said, "I respectfully dissent." And Ashish Jha, a physician and a professor at the Harvard T.H. Chan School of Public Health, added, "All red-blooded, patriotic Americans should use 'healthcare.'"

So should it be "healthcare" or "health care"? The Daily Briefing asked industry stakeholders to make their best case—and learned the debate really comes down to modifiers.

Jha told the Daily Briefing, "Healthcare is a single word because it’s a single concept. 'Health' is not meant as modifier to 'care' in this context—it's not like we're trying to say health care as opposed to education care or car care.  And no one calls it Obama Care. It's Obamacare." Those who think it should be two words, Jha quipped, "are wrong and should be stopped."

Austin Frakt, a health economist, contributor to the New York Times' "The Upshot," and editor-in-chief of The Incidental Economist, disagreed. "Health" and "care" are two separate words, Frakt said, and the adjective "health" modifies the noun "care." He added, "It's the same thing with 'dental care' or 'pet care' or 'lawn care.' If we give in to the hokey 'healthcare,' where would it stop? We'd open ourselves up to absurdities like 'intensivecare' and 'woundcare.' Let's stop this madness before it begins."

Baker made an additional point: That the potential for additional modifiers means "health care" needs to be two words. "For example, 'mental health care' is care for mental health," Baker said. "'Mental healthcare' would mean that the healthcare itself is mental, which is not a thing."

Advisory Board's style is to always use two words, except when referring to an institution that uses one word in its formal name. We'll keep an eye on whether AP changes its policy, but we're sticking with "health care" for now.

Editor's note: And we may stick with "health care" even if AP changes its official style. Some hills are worth dying on.