Crescent Moon
noun
What's a "third day moon"? It's a crescent moon. A crescent moon is the newly visible moon that appears on the third day of the month in the lunar calendar that Japanese people used back in the day.
This word combines the vocab words 三日 and 月, so it uses their readings, except they're slightly different here: there's no small っ in 三日, and 月 has rendaku. Sounds complicated, but the changes actually make the word easier to pronounce. (Try it yourself — みかづき is easier to say than みっかつき, right?) Here's a mnemonic to remember the みか and づ parts, just in case:
You're out with your friend Mika one night when a crescent moon appears. What do you say to her? "Mika, dude (みかづ)! It's a crescent moon!"
Hint: To get the character づ, type "du" on your keyboard.
今日は三日月です。
There's a crescent moon today.
三日月のような目をしてますね。
You have eyes that are like a crescent moon.
山の上から三日月がよく見える。
You can see the crescent moon well from the top of the mountain.