decigram, (kokuji)
瓰 is a Japanese-made kokuji that represents a decigram, a unit of weight equal to one-tenth of a gram. Its meaning is purely metrological and has no abstract extensions.
瓰 is a modern kokuji created in Japan by combining 瓦 (gram) with 分 (part, minute) to represent a decigram (one-tenth of a gram). The character was coined for metric unit notation and has no ancient origin.
瓦 stands for 'gram' in metric kanji, and 分 means 'part' or 'tenth'. Together they form a decigram: a tenth of a gram.
For デシグラム, the reading is the direct katakana loanword 'decigram'. Think of the 'deci-' in decimal matching the 分 (tenth) inside the gram 瓦.
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