Home › Words › F › firefoxerfirefoxerfirefoxer means one who uses the web browser Firefox.EtymologyFrom Firefox + -er.nounOne who uses the web browser Firefox.e.g.“Follow that up with a polite email to the site’s webmaster, asking him to test that page in Firefox. You may be helping a lot of fellow Firefoxers.” — 2005, Scott Granneman, Don’t Click on the Blue e!: Switching to Firefox, O’Reilly Media, →ISBN, page 182:Definitions & examples from Wiktionary (CC BY-SA 3.0).