imperceptible
01
察觉不到的, 难以感知的
so slight or gradual that it cannot be noticed
例子
The temperature dropped by an imperceptible degree.
温度下降了难以察觉的一度。
Her smile was imperceptible, more felt than seen.
她的微笑难以察觉，更多是感受到而非看到。
词汇树
imperceptible
perceptible
percept
