Tsuki in Chinese / Japanese...

花鳥風月 is the Japanese Kanji proverb for “Beauties of Nature.”

The dictionary definition is “the traditional themes of natural beauty in Japanese aesthetics.”

The Kanji each represents an element of nature that constitutes beauty in traditional Japanese art and culture.

The Kanji breakdown:
花 = ka = flower (also pronounced “hana”)
鳥 = chou = bird (also pronounced “tori”).
風 = fuu = wind (also pronounced “kaze”).
月 = getsu = moon (also pronounced “tsuki”)

月 is how to write the title for “moon” in Chinese, Korean Hanja, and Japanese Kanji.

月 is also used to refer to the month. This is because China traditionally uses a lunar calendar, so saying “next moon” is the same as saying “next month” etc.
In modern Chinese and Japanese and old Korean, the character for a number is put in front of this moon character to represent western months. So “one moon” is January “two moons” is February etc.

If you are wondering, in the east Asian way to write dates, the character for “sun” or “day” is used with a number in front of it to express the day of the month. So “ten moons, one sun” becomes “October 1st” or “10/1” (this date happens to be Chinese National Day - The equivalent of Independence Day in the USA, Canada Day, or the Queen's Birthday).

In Japanese, 月 can be a surname that romanizes as Tsuki, Tsukizaki, or Takagetsu.

月の心 means “Mind like the Moon” or, more directly translated, “Moon of Mind.”

月の心 is a phrase used in Zen Buddhism and some Japanese martial arts.