A Story
紅顏 = red color (紅 red + 顏 color)
知己 = one with deep connection
(知 = know/understand + 己 = oneself)
知己 - directly translates to "know" and “self", but together there's a little more meaning to it, in that it can indicate the degree to which someone can know you.
For someone to know you, closer than family, closer than friends, someone you are comfortable with, that you can share your life with, that knows you... Well, that is a different type of closeness and intimacy. That close person is a 紅顏知己.
The way Dad described these words culturally, there’s feeling and weight implied to the closeness of this person.
“Soulmate” is a thought, and if you're down to get into Plotinus and the 'soul bowl', and cross cultural contests, that's a further conversation – peaccce&:D
Date Added: 3/14/2021