used in Chinese place names
埔 is a kanji used primarily in Chinese place names. Its standalone meaning is tied to flat land or a plain, but it is not used as an independent word in Japanese.
埔 combines 土 (earth, ground) with 甫, which likely contributes a phonetic element. The character is associated with flat land or a plain, consistent with its use in place names.
The left side 土 means earth or ground, and the right side 甫 looks like a garden plot. Picture a flat piece of earth marked out as a place on a map.
For ホ, imagine a flat plain where a gardener uses a hoe (ホ) to work the earth. The hoe sound cues ホ while the earth 土 ties back to the kanji's meaning.
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plains indigenous peoples (of Taiwan); plain aborigines