Op

Op is a short form used in a variety of contexts to denote different concepts depending on the domain. Common uses include Original Poster or Original Post in online discussions, and opus in classical music, among others.

In online forums and Q&A sites, the term OP (original poster) denotes the user who started a thread or posted the initial question or message. The term is often used to attribute subsequent replies or to request clarification from the OP. In many communities, the OP’s comments or edits can signal a shift in the discussion’s focus. The lowercase op is sometimes seen in prose, but OP is more common in written discussions and notation.

In classical music, Op. stands for opus, from Latin for “work.” It is used as a cataloging number that identifies a specific composition within a composer’s output, for example Beethoven’s Piano Sonata Op. 27. Composers may publish multiple opuses, and the cataloging system varies by country and edition. The opus number helps musicians, scholars, and collectors reference a work consistently.

In online gaming and anime or manga communities, OP or op is commonly used to describe something that is overpowered—that is, disproportionately powerful or effective within a game or story. The term can be evaluative, used to critique or humorously note imbalance, and it may motivate discussions about balancing changes in games or narratives.

Other uses of Op or OP exist in various technical and cultural contexts, but the three senses above—Original Poster/Original Post, opus in music, and overpowered in media discussions—are among the most widely encountered.