Stomach
This radical means stomach, since it kind of looks like one. See the big stomach sitting on top of some intestines that snake downwards? Just keep in mind this radical is specifically for the stomach, and the stomach only — not all the other stuff attached to it.
You could also remember it with a mnemonic: To eat a rice paddy the size of the moon, you'd need a pretty impressive stomach. Every doctor and scientist in the world would probably be jostling to get a look at your incredible stomach and see how you managed to fit a moon-sized rice paddy into it.