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field; plain; prairie; tundra; moor; wilderness
「原」 has other readings with different meanings.
広い原っぱで遊んだ思い出がある。
I have memories of playing in the wide field.
広い草原を馬で走ってみたいな。
I want to ride a horse across the grassland.
原野に立つと気持ちがいいよね。
Standing in the field feels good.