pylorus
noun
py·lo·rus pī-ˈlȯr-əs 
pə-
plural pylori pī-ˈlȯr-ˌī
-(ˌ)ē,
pə-
: the muscular opening from the vertebrate stomach into the intestine
Example Sentences
Recent Examples on the Web This is key, because once popped back open, those arms span wider than two centimeters—the diameter of the human pylorus, the gateway to the intestines. 
Wired, 4 Dec. 2019
Wired, 4 Dec. 2019 Word History
Etymology
Late Latin, from Greek pylōros, literally, gatekeeper, from pylē
First Known Use
1565, in the meaning defined above
Medical Definition
pylorus
noun
py·lo·rus pī-ˈlōr-əs, pə-ˈlȯr-
plural pylori -ˈlō(ə)r-ˌī, -(ˌ)ē
: the opening from the vertebrate stomach into the intestine see pyloric sphincter