(arch.) state during Zhou dynasty
豳 is an archaic proper noun referring to a state during the Zhou dynasty. It has no clear standalone meaning beyond that historical reference.
豳 is an ancient character used as a place name. The modern form visually contains 山 (mountain) over a doubled pig component 豩, but the exact historical development is uncertain.
Picture two pigs 豩 under a mountain 山: this is the ancient state of 豳, perhaps a place where pigs were kept in the hills.
For ヒン, imagine the two pigs under the mountain making a soft 'hin' sound, like a pig's snort: hin -> ヒン.
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