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.
(..) Can we therefore conclude that humans are concerned more with "having"... ...than "being". Lucy. what did you do with my stomach? Nothing! Just a little horizontal slit. It's very well done and you'll find in a month, this scar is practically invisible. You'll be in shape for the beach next summer. I don't care about the scar. Is it, uh...is it why we opened you up? Rest assured, we didn't harvest your organ or anything and we merely slipped a little package in your lower stomach. It's a...it's a new drug the kids in Europe is gonna love, believe me. - What's that? (..)2014 Lucy