Scots language (ISO 639 alpha-3: sco)

Synchronous Connection Oriented protocol used for audio devices in the Bluetooth protocol stack

Silver Chips Online, a high school newspaper

Synthetic Crude Oil, a type of crude oil

Space Cowboy Online, an action-based online 3D Space Shooter game

SCO Group, the company originally known as Caldera Systems that acquired several assets from Santa Cruz Operation and got involved in a number of high-profile lawsuits

Singapore Chinese Orchestra

Scorpius, abbreviation for the constellation

Shareable Content Object, an organization of web-based courseware

Osco Drug, a chain of pharmacy stores

Southern College of Optometry in Memphis, Tennessee

SCO OpenServer, an operating system made by the above companies

Selected Characteristics of Occupations, a companion volume to the U.S. Department of Labor's Dictionary of Occupational Titles

Used as an unofficial country code for Scotland (the correct codes are those for the UK as a whole).

Angers SCO, French football club

.sco, the proposed national internet TLD for Scotland

Shanghai Cooperation Organization, an Eurasian inter-governmental organization

Scottish Chamber Orchestra

Santa Cruz Operation, a company founded in 1979, renamed Tarantella, Inc. in 2001