a horse of another (or different) colour a thing significantly different.
1975Sam SelvonMoses Ascending Two or three is okay, but when you start bringing in a battalion, it is a horse of a different colour.
英语词组固定搭配大全包含15956条英汉双解词组，基本涵盖了全部常用英文词组、短语的翻译及用法，是英语学习的有利工具。