Take this medication 'on an empty stomach'. [=when your stomach is empty because you have not eaten for a time]
When I had the flu, just the thought of eating made me 'sick to my stomach'. [='nauseous']
She felt a flutter in 'the pit of her stomach' when he walked through the door.
(..) a pain in the butt at times... And trust me, I know. But this cat proved to me without a doubt that his heart is bigger than his stomach. -To Alex. -To Alex. Enough! Stop it! What do you think? Should we head back to New York? (..)2005 Madagascar