centigram, (kokuji)
甅 is a Japanese-made kanji (kokuji) that represents a centigram, a unit of mass equal to one hundredth of a gram. Its meaning is entirely tied to this specific measurement.
甅 is a kokuji created in Japan by combining 瓦 (gram) with 厘 (rin, a small unit), to represent a centigram. The components were chosen for their semantic relevance to small weight measurements.
The outer 瓦 is used for gram-related kanji, and inside is 厘, a small unit. Picture a tiny weight inside a gram container: a centigram.
For センチグラム, think of a centigram as a 'centi-gram'. The reading is exactly the borrowed word センチグラム, so remember it as the Japanese pronunciation of 'centigram'.
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