tonnage, (kokuji)
噸 is a Japanese-made kokuji that represents a unit of weight: a ton. Its meaning is narrowly focused on tonnage.
噸 is a kokuji created in Japan by combining the mouth radical 口 with the character 頓, which provides the phonetic reading トン. It was coined to represent the Western unit 'ton'.
The mouth radical 口 hints at a spoken word or unit name, while 頓 gives the sound. Together they form a character for the heavy unit 'ton'.
For トン, the reading is exactly the English word 'ton'. Imagine a giant weight labeled 'TON' dropping into the mouth 口 of the character.
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