Can I get definition of infundibulum?

Funnel-shape anatomy. In medicine, the term infundibulum is an anatomical term, referring to an organ part with a cavity shaped like a funnel. For example, the end of the fallopian tube, next to the ovaries, is termed infundibulum. Another example is the outgrowth of the brain that becomes the pituitary gland. It is also the entrance into the maxillary sinus.