- ♦♦1) Co. is used as an abbreviation for company when it is part of the name of an organization.
...the Blue Star Amusement Co.Syn:2) Co. is used as a written abbreviation for county before the names of some counties, especially in Ireland.
...Co. Waterford.3) PHRASE: n-proper PHR You use and co. after someone's name to mean the group of people associated with that person. [INFORMAL]
Wayne Hussey and co. will be playing two live sets each evening.
English dictionary. 2008.