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).
Do you remember the formula for finding the geometric mean?
The arithmetic mean of this sequence is 5.
等差中項 explicitly means 'arithmetic mean', another common compound.
mean proportional; geometric mean
Compound of 中 (middle) and 項 (term, item), directly reflecting the mathematical concept of a middle term in a proportion or sequence.