noun
national script; official writing system
Refers to a country's officially recognized writing system or script. Often used in historical or comparative contexts.
漢字は中国の国字の一つです。
Kanji is one of China's national scripts.
noun
kana; Japanese syllabary
In Japanese contexts, 国字 can specifically mean kana (hiragana and katakana), the syllabic scripts developed in Japan, as opposed to kanji.
平安時代には国字である仮名が広く使われるようになった。
During the Heian period, kana, the Japanese syllabary, came to be widely used.
noun
Japanese-made kanji; kokuji
The most common modern meaning: kanji characters created in Japan following Chinese character formation principles, such as 峠 (tōge) or 働 (hataraku).
「峠」や「畑」は日本で作られた国字です。
Characters like 峠 and 畑 are kokuji, kanji created in Japan.
Kana refers specifically to hiragana and katakana. 国字 (sense 2) can be used as a broader term for the Japanese syllabary.
Compound of 国 (kuni, 'country') and 字 (ji, 'character'). The meaning has shifted over time: originally 'national script', later 'kana', and now primarily 'kanji created in Japan'.