dilatationnoun [ U ]
uk/ˌdɪl.əˈteɪ.ʃən/us/ˌdɪl.əˈteɪ.ʃən/specializedthe process of becoming wider or more open, or the act of making something do this:
Dilatation of blood vessels is always associated with increased blood flow and increased blood pressure.
Balloon dilatation is a safe and effective treatment for patients with tight urethral strictures.