お腹・お中|おなかonaka[0]heiban (flat)

1. nounbelly; abdomen; stomach
   いいえ、結構けっこうです。お腹なかが一杯いっぱいですから。↗

   No, thank you. I've had enough.

• Synonym腹はらNeutralA blunter, more neutral word for the belly, used more by men. It also covers one's mind and real intentions, as in 「腹を探る」, which 「お腹」 does not.
• Synonym腹部ふくぶWrittenFormal, medical term for the abdomen as a body region, as in 「腹部の痛み」; at home in clinical and other formal contexts, spoken or written.
• RelatedぽんぽんCasualThe same word as above; it matches 「お腹」 only in this childish 'tummy' sense. As an onomatopoeia for tapping or popping sounds, it has nothing to do with 「お腹」.

In everyday speech 「お腹」 is the default word for the belly. 「腹」 is blunter and more masculine, 「腹部」 is the term for medical or formal settings, and 「ぽんぽん」 is the childish, affectionate choice.

Usage comparisons are AI-assisted and cross-checked by multiple models; for study reference only

1. 体からだの、胸むねより下したの部分ぶぶん。
2. 食べ物たべものを消化しょうかする内臓ないぞうのある所ところ。