Unofficial means not formally approved, authorized, or recognized by people in charge. When something is unofficial, it exists or happens without official permission or endorsement, even though it might be widely known or accepted.

If students create an unofficial school newspaper without the principal's approval, it's still a real newspaper, but it doesn't represent the school officially. An unofficial school record might be when everyone knows a student ran the fastest mile ever, but it wasn't recorded during an official timed event. A group of friends might hold an unofficial chess tournament during recess, meaning it's real and fun, but not sanctioned by the school chess club.

The word often appears in news reports: journalists might cite unofficial results before election officials have certified them, or report unofficial estimates of crowd sizes before organizers release official numbers. These unofficial figures are often accurate, but they haven't been formally confirmed yet.

Sometimes unofficial suggests something operating in a gray area, neither fully approved nor exactly forbidden. Other times it simply means informal or casual, like an unofficial class reunion organized by former students rather than the school.