There were many anonymous posts on that bulletin board.
He was buried in history without a name.
He posted on the internet forum anonymously, without giving his name.
That cat is being kept without ever being given a name.
有名 means 'famous, having a well-known name,' the opposite of 名無し's sense of having no name or identity at all.
実名 is one's real, disclosed name, contrasting with 名無し, which refers to having no name or hiding one's identity.
無名 means 'unknown/obscure' (lacking fame), whereas 名無し literally means 'without a name,' so a famous person can still be 無名 in some field but not 名無し.
Standard kanji spelling.
Alternate kanji spelling; less common than 名無し.
Compound of 名 (na, 'name') + 無し (nashi, 'without'), an old form of ない. The spelling 名無し is the standard representation.