厘 is a measure word for very small units, commonly used to express 0.1% (one-tenth of a percent) in interest rates, fees, or differences. It can also represent 0.001 in decimal fractions or the minimal amount in figurative phrases like 一厘之差 (a trivial difference). Unlike regular classifiers like 个, 厘 is a unit word that typically follows a number and may be followed by the noun being measured (e.g., 两厘利息 'two percent per mille interest').