- a dilating or being dilated, as of the pupil of an eye, a blood vessel, or the cervix during childbirth
- a dilated part
- a. The act of expanding or enlarging or the state of being expanded or enlarged: dilation of the cervix during labor.b. The condition of being abnormally expanded or enlarged, as of an organ, orifice, or tubular structure in the body.
- A lengthy spoken or written discussion on a topic: “an Edith Whartonesque dilation on a social class steeped in hypocrisy” (Caroline Seebohm).