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abdomen; stomach; lower parts; under parts
「下腹」 has another reading with different meanings.
下腹が痛くて困った。
My lower abdomen hurt, which was troublesome.
下腹を引き締める運動を教わった。
I learned exercises to tighten my lower abdomen.
ヨガで、下腹を意識して呼吸した。
In yoga, I consciously breathed into my lower belly.