Anticitizen

Anticitizen is a term used by The Combine to designate a person as a threat to their control. The Combine use the term 'anti citizen' because the behavior of anticitizens is the opposite of that of citizens (or at least, the Combine's definition of a citizen as a person under their rule who does not resist them). Each anticitizen is given a number representing how dangerous they are to the Combine, and ranked in descending order. Gordon Freeman is Anticitizen One, and thus the living being who poses the most danger to the Combine.