Words for "stomach" (お腹、胃袋、etc.)

Question

I noticed that there are many words that can translate to "stomach" in Japanese, including:

胃{い}・胃{い}袋{ぶくろ}・お腹{なか}・腹{はら}・胃{い}の腑{ふ}・胃{い}腸{ちょう}

What is the difference between these, and how do I know which is proper to use in any situation?

Also, my gut feeling (no pun intended!) is that お腹 is polite and used when talking about hunger, 腹 is more like "belly" (more general than "stomach"), and 胃腸 is medical/academic. Is that correct?

Answer 1

• 胃: A digestive organ located between the esophagus and the duodenum. English "stomach" refers to both this specific organ and the abdomen, but you should make clear distinction in Japanese.
• 胃袋: A more casual word for 胃. Not used in formal/medical documents.
• 腹: Abdomen.
• お腹: Abdomen. Sounds more mild and politer than 腹.
• 腹部【ふくぶ】: Abdominal area. (formal and/or technical, safely used in medical contexts)
• 胃の腑: Very rare. You may find this in certain uncommon idioms.
• 胃腸: Stomach and intestine (vaguely referring to the digestive system). It's a vague (and non-academic) word typically heard in ads and TV variety shows. In medical contexts, more academic terms such as 上部【じょうぶ】消化管【しょうかかん】 ("upper gastrointestinal tract") are preferred.