Tea is said cha in Japanese.
As you have expressions and idioms using "tea" in English, Japanese also use "cha" in daily conversation. For examples, "mucha (literally, no tea)" refers to reckless, "ocha wo nigosu (literally, make tea cloudy)" does fudge an issue, and "chairo (literally, tea color)".
Here’s a question for you. In this case, what kind of color would you think of?
Japanese tea is usually called green tea, so you might come up with green. But, surprisingly or not, chairo refers to brown. Why not, green!?
Imagine that you use tea for dyestuff. What color would you get? Or, imagine that you wipe spilt green tea on a table? Don’t you see brown stain on the towel? This is the origin of the word chairo.
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Does it make sense? Anyway, that’s it for today’s Japanese lesson!