CO: Certificate of Origin: CO: Colchester (postcode, United Kingdom) CO: Cellular One: CO: Clean Out (sewers/drains) CO: Charlotte Observer (newspaper) CO: Cargo Operations: CO: Certificate of Occupancy: CO: Cash Order: CO: Corporación (Spanish) CO: Collection Officer: CO: Comercializadora de Occidente SA (Guatemala) CO: Consumer Ombudsman (UK) "Co" is just an abbreviation for the word "company." A company is an association of people working in a commercial business. This can be a limited liability company, sole proprietorship, or another structure. Abbreviating "company" as "co" does not have a specific meaning regarding a business's legal structure. About Incorporated Businesses Corporations (Inc., Ltd., Co.) The primary difference between this type of company is that it is owned by stockholders. There are directors or officers that are appointed and help manage the a. : one that is associated in an action with another : fellow : partner. coauthor. coworker. b. : having a usually lesser share in duty or responsibility : alternate : deputy. copilot. 4. : of, relating to, or constituting the complement of an angle. C-corporation – Incorporated business composed of shareholders, directors, and officers S-corporation – Incorporated business that is taxed as a pass-through entity e32WMGB.