A minuscule amount; an extremely small quantity, often referred to in measurement or dosing contexts (common in scientific/technical use).
この薬は微量ずつ与える必要がある。
This medicine needs to be administered in tiny amounts.
研究では微量の汚染物質でも影響が出ることが示された。
The study showed that even trace amounts of contaminants can have effects.
微量成分の測定には高感度の装置が必要だ。
Measuring trace components requires highly sensitive equipment.