noun
round-down function; truncation function
Computing term for a function that discards fractional parts or lower-order digits, effectively rounding down toward zero or a specified precision.
この計算ソフトには切捨て機能がついています。
This calculation software has a round-down function.
切捨て機能を使って小数点以下を切り捨ててください。
Please use the round-down function to discard the decimal places.
Compound of 切捨て (kirisute, 'cutting off, discarding') and 機能 (kinō, 'function'). The exact historical derivation is uncertain; the term is a modern computing expression.