How can we say "a forgotten war" in Latin?
You know what I'm really getting at: I'm asking "How to make a deponent passive in meaning?" but with a specific and puzzling example. Oblīvīscor, "I forget", is a deponent verb, so oblītus can only mean "so-and-so having forgotten [something]".
Didn't the Romans ever feel the need for a past participle to express the idea of having been forgotten, generally, without specifying who forgot? Did no Roman grammarian ever curse this gap in the language?