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cause; seed; origin
variety; kind
counter for varieties
「種」 has other readings with different meanings.
この種の植物は日当たりの良い場所が好きだ。
This type of plant likes sunny places.
絶滅危惧種を保護する活動に参加した。
I participated in activities to protect endangered species.
心配の種が一つ減ったよ。
One cause for worry is gone.