correct character; standard form
Refers to a kanji written in its officially recognized or historically correct shape, as opposed to variant or erroneous forms. Also used for a kanji used with its original meaning.
The correct form of this kanji is written in the old character style.
traditional kanji; unsimplified kanji
Specifically refers to the traditional, pre-simplification form of a kanji, often contrasted with 新字体 (simplified form) or 略字 (abbreviated character).
The traditional form of '国' is '國'.
proofreader of characters (historical Chinese official)
Historical term for an official in China responsible for verifying the correctness of written characters in books. Rarely used in modern Japanese outside historical contexts.
異体字ではなく、正字を使ってください。
Please use the standard character, not a variant.
正字と新字体の違いを調べる。
I look up the difference between traditional and simplified kanji.
In the old Chinese system, an official called 正字 proofread the characters in books.
旧字体 specifically means 'old character form' and is often synonymous with 正字 in the context of traditional vs. simplified kanji.
orthography
From 正 (correct) + 字 (character). The term has been used historically in both Japanese and Chinese contexts to denote the standard or correct form of a character.