origin of a character; character etymology
Refers to the historical origin and structural composition of a Chinese character, often discussed in kanji studies. Sense 2 (composition) is closely related and merged here.
When you look into the origin of a kanji, you can understand how it was formed.
Chinese character from which a kana is derived
Specifically used for the original kanji that gave rise to a kana character, such as 安 → あ or 以 → い.
The character origin of the hiragana 'a' is the kanji '安'.