The radical tsuki stands for moon or month when used at the right side of a character. However the radical niku肉 that stands for body or body-part is in many cases simplified to 月 and thus looks equal as "moon".
The radical niku is typically at the left side of a composition and drawn as: 月, which looks equal to: "moon, month 月" but has the meaning 'body part'.
Tip: Go to the radicals that are contained in this character and learn all the characters with this radical systematically!
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