Refers to solid or semi-solid remains left after a process, such as coffee grounds, tea leaves, or industrial residue. Often used in technical or formal contexts.
コーヒーの残渣を捨ててください。
Please throw away the coffee grounds.
They remove the residue left in the filter.
この液体には残渣が多く含まれている。
This liquid contains a lot of sediment.
研究者は反応後の残渣を分析した。
The researcher analyzed the residue left after the reaction.
After evaporation, residue remained at the bottom of the container.
沈殿物 specifically means sediment that has settled at the bottom of a liquid, whereas 残渣 covers any leftover solid residue from a process, not just settling.
Compound of 残 (ざん, 'remain') and 渣 (さ, 'dregs'). The kanji 渣 is relatively uncommon and primarily appears in this compound.