n (strictly) The act of identifying (i.e., which one, which thing).
n (broadly, often) The combination of identifying (which one, which thing) and validating the identity (proving or confirming it); identifying and authenticating viewed as a unitary concept in cognition.
n The state of being identified.
n (countable) A particular instance of identifying something.
n A document or documents serving as evidence of a person's identity.
n A feeling of support, sympathy, understanding, or belonging towards somebody or something.