Most anatomical terms are descriptive in Latin or Greek. However, “Eustachian” doesn’t mean anything. It is a term called an eponym. Traditionally, in anatomy the person who first discovered or described an anatomical structure was honored by having that structure named after them. Bartolommeo Eustachi (Eustachius), a sixteenth century Italian anatomist, described the tube that connects the middle ear cavity with the throat. It helps equalize pressure on either side of the ear drum. When your ear feels blocked as often happens when rapidly ascending or descending in a plane, you yawn to “pop” your ears. What you are doing is widening the Eustachian (auditory) tube to allow passage of more air.