unofficial

adjective

un·​of·​fi·​cial ˌən-ə-ˈfi-shəl 

also -ō-

: not authorized or acknowledged by a government, group, class, or society : not official

unofficial results

an unofficial policy

unofficially adverb

Examples of unofficial in a Sentence

Recent Examples on the Web

All those little unofficial participants, the sloops and ketches that will join the festivities, will be restricted to nine holding areas. — Christopher Bonanos, Curbed, 30 June 2026

Nike likely has much more in store to celebrate the ruby anniversary, much of which should surface via official or unofficial channels as the occasion draws nearer. — Ian Servantes, Footwear News, 30 June 2026

Fourth of July weekend is the unofficial start of the summer festival season, which includes open-air shows at stadiums and amphitheaters. — Christopher Arnott, Hartford Courant, 27 June 2026

The flamingo — one of several endangered bird species whose natural habitat could be destroyed by development on such a massive scale — has quickly become the protest’s unofficial mascot. — Larry Luxner, Sun Sentinel, 29 June 2026

Word History

First Known Use

1784, in the meaning defined above

Rhymes for unofficial

• artificial
• beneficial
• cicatricial
• interstitial
• nonjudicial
• nonofficial
• prejudicial
• sacrificial
• superficial
• extrajudicial
• semiofficial
• initial

Medical Definition

unofficial

adjective

un·​of·​fi·​cial ˌən-ə-ˈfish-əl 

: not official

specifically : of, relating to, or being a drug not described in the United States Pharmacopeia and National Formulary compare nonofficial, official