zero element
In abstract algebra, the element of a set that, when combined with any other element under a given operation, leaves that element unchanged. Used in contexts such as additive identity in rings or vector spaces.
ベクトル空間の零元は、加法に関する単位元である。
The zero element of a vector space is the identity element with respect to addition.
単位元 is the identity element for a general operation, while 零元 specifically refers to the additive identity (often denoted 0).
nilpotent element
From 零 (zero) + 元 (element). A modern mathematical term, likely a calque from English 'zero element' or German 'Nullelement'.