(computing, retronym) A naming convention in older MS-DOS and Microsoft Windows operating systems, restricting filenames to a maximum of eight characters followed by a period and a three-character file extension.

The decade of the 1980s. / Temperatures from 80 to 89 degrees.

Alternative spelling of 80s

(Canada, US) A toll-free number or a long-distance telephone numbers; using any of North American toll-free area codes 800, 888, 877, 866, 855, 844 or 833.

(inorganic chemistry) A saturated solution of ammonia in water; ammonium hydroxide 28% (w/w as ammonia).

(Canada, US) A toll-free telephone number.

plural of 800 number

(idiomatic) An entity that dominates its environment. / (idiomatic) Something dangerous, menacing, or frightening that is obvious but not addressed.

(athletics) A middle-distance running race over 800 metres.

An IEEE standard, IEEE 802.11e-2005, that adds QoS (Quality of Service) features and multimedia support to the existing 802.11b, 802.11g, and 802.11a wireless networks.