鲜艳度的英文：
vividness

A vivid memory,imagination,etc
犹新的记忆、活跃的想像力.

A vivid description,recollection,dream
生动的描述、清晰的回忆、清楚的梦

It was a long slender stick of vivid yellow.
那是一根鲜黄色的又细又长的粉笔。

She loved to wear vivid characterization.
她喜欢穿鲜艳的颜色。

Only the vivid red hair ever stood out.
只有鲜艳的红头发非常令人注目。