If a fireman came to work in a police outfit or clown suit, that would be a clear case of nonconformity. Where there’s nonconformity, there’s difference.
When everyone is acting or dressing exactly the same, there’s conformity, not nonconformity. Nonconformity means that someone is doing things differently from the norm. People in authority tend to dislike nonconformity, because it makes people harder to control. Someone who demonstrates nonconformity most of the time is a nonconformist. Too much nonconformity can create chaos, but without a little nonconformity, life would be pretty boring.
failure to conform to accepted standards of behavior
a lack of orthodoxy in thoughts or beliefs
unorthodoxy as a consequence of not conforming to expected standards or values
lack of harmony or correspondence