noun
mean; middle term
Mathematical term for the middle term in a proportion or sequence; used in contexts such as 比例中項 (geometric mean) or 等差中項 (arithmetic mean).
比例中項を求める公式を覚えていますか。
Do you remember the formula for finding the geometric mean?
この数列の等差中項は5です。
The arithmetic mean of this sequence is 5.
等差中項 explicitly means 'arithmetic mean', another common compound.
Compound of 中 (middle) and 項 (term, item), directly reflecting the mathematical concept of a middle term in a proportion or sequence.