Mathematics prefix meaning 'identical' or 'identity', used in terms like 恒等式 (identity equation) and 恒等変換 (identity transformation).
This equation holds identically.
The identity mapping maps every element to itself.
identity (mathematics)
identity mapping; identity function
identity transformation
identity relation
identity function; identity operator
identity operator
Standard kanji spelling for this mathematical prefix.
Compound of 恒 (constant, permanent) and 等 (equal, same). The exact historical derivation as a mathematical term is uncertain, but it is used to translate the Western mathematical concept of identity.