infundibulum

https://doi.org/10.1351/goldbook.10851

Anatomical funnel-shaped opening, often referring to the hollow stalk that connects the hypothalamus and the posterior pituitary gland, or to the portion of the Fallopian tube that receives the ovum.

Source:
PAC, 2016, 88, 713. (Glossary of terms used in developmental and reproductive toxicology (IUPAC Recommendations 2016)) on page 769 [Terms] [Paper]