a: to publish, announce, or advertise by or as if by use of a placardb: to denounce by public noticec: to enter on a public listingd: to forbid (property) to trespassers under penalty of legal prosecution by notices placed along the boundaries
韋氏詞典裡posting的第三個意項就是“網上釋出的訊息”：
something (such as an announcement) that is posted online
po來自於post/posting，在這裡是主貼/文章的意思。“po主”就是貼主，“原po”就是主貼的意思。
post原意是動詞，“釋出訊息”的意思，比如釋出訊息，釋出職位資訊都可以用post。
其名詞形式是posting，“被髮布的訊息”。
韋氏詞典裡post的第一個意項就是“釋出訊息”：
a: to publish, announce, or advertise by or as if by use of a placardb: to denounce by public noticec: to enter on a public listingd: to forbid (property) to trespassers under penalty of legal prosecution by notices placed along the boundaries韋氏詞典裡posting的第三個意項就是“網上釋出的訊息”：
something (such as an announcement) that is posted online現在外文網路上，posting經常被縮寫為post或者po，反而posting這個原詞因為字母太多很多人懶得打。