1. positive identification - evidence proving that you are who you say you are; evidence establishing that you are among the group of people already known to the system; recognition by the system leads to acceptance; "a system for positive identification can prevent the use of a single identity by several people"
positive identification number, number - a numeral or string of numerals that is used for identification; "she refused to give them her Social Security number"
identity card, card - a card certifying the identity of the bearer; "he had to show his card to get in"
countersign, password, watchword, parole, word - a secret word or phrase known only to a restricted group; "he forgot the password"
identification - evidence of identity; something that identifies a person or thing