CO
Defined in 2 dictionaries — U.S. Code, Black's (1910)
United States Code
42 U.S.C. § 7602 — in this chapter (4 versions over time)
The term “CO” means carbon monoxide.
Black's Law Dictionary
Henry Campbell Black, M.A. · 1910
A prefix to words, meaning "with" or "in conjunction" or "joint;" e. g., co-trustces, co-executors. Also an abbreviation for "county," (Gilman v. Sheets, 78 Iowa, 499, 48 N. W. 299,) and for "company," (Rallroad Co., v. People, 155 III. 299, 40 N. E. 599.)