dilatio
Dilatio is a Latin noun meaning enlargement, widening, or dilatation. In medical Latin, it denotes the process or result of widening a passage or orifice. In English medical terminology, the direct Latin noun is rarely used; its concepts are expressed with dilation or dilatation, derived from the same root as the Latin dilatare, “to widen.” The term appears in historical texts and in modern discussions of anatomy and physiology where Latin wording is encountered.
In clinical usage, dilatio refers to the widening of hollow structures such as vessels, ducts, or passages.
The term also appears in historical and scholarly contexts to describe observed widening in anatomical structures.