Every year heading into WWDC, one thought on many Mac fans' minds is what Apple will choose as the name for the next version of macOS. The tradition dates all the way back to the beginning of Mac OS X with big cat names like Leopard, and Apple eventually shifted to California-themed names with the unveiling of OS X Mavericks.Apple has yet to announce the name for macOS 27, but macOS Emerald and macOS Big Bear have emerged as two speculative possibilities.While it will have a new Siri app and other Apple Intelligence enhancements, macOS 27 will reportedly be focused on bug fixes and stability improvements. In other words, it will be a refined version of macOS Tahoe. For this reason, macOS Emerald could be a fitting name for macOS 27, given that Emerald Bay is part of Lake Tahoe. This would be similar to how macOS High Sierra was a refined version of macOS Sierra.macOS Big Bear is another speculated name, as MacRumors contributor Aaron Perris discovered that the filename for Apple's WWDC 2026 hashtag graphic on X mentions "Project Big Bear." macOS Big Bear would refer to Big Bear Lake in California. However, the filename could obviously end up being unrelated to macOS 27 naming.Back in 2014, we discovered more than 20 California-themed trademark applications filed by various limited-liability companies, which were all but certain to be shell companies created by Apple to hide its identity. Over time, some of the trademarks like Yosemite, Sierra, Mojave, Monterey, Mojave, Ventura, Sonoma, and Sequoia were indeed used as macOS names, while trademark applications for other names were abandoned.Apple has still proceeded to use some of the names with abandoned trademark filings as macOS names, such as Big Sur in 2020. So, there is still a possibility that macOS 27 will use one of the names that Apple had filed to protect many years ago.Here is a list of the remaining words that Apple had filed: California Condor Diablo Farallon Grizzly Mammoth Miramar Pacific Redtail Redwood Rincon Shasta Skyline TiburonOf course, there is no guarantee that Apple will ever use any of these names. It is simply fun to think about the possibilities each year.Apple will unveil macOS 27 during its WWDC 2026 keynote on Monday, June 8.Related Roundups: macOS 27, WWDC 2026Related Forum: Apple, Inc and Tech IndustryThis article, "macOS Emerald to macOS Big Bear: What Will Apple Name macOS 27?" first appeared on MacRumors.comDiscuss this article in our forums