Noun | 1. | dilation - a lengthy discussion (spoken or written) on a particular topic discussion, discourse, treatment - an extended communication (often interactive) dealing with some particular topic; "the book contains an excellent discussion of modal logic"; "his treatment of the race question is badly biased" |
2. | dilation - the act of expanding an aperture; "the dilation of the pupil of the eye" enlargement, expansion - the act of increasing (something) in size or volume or quantity or scope vasodilation - dilation of blood vessels (especially the arteries) mydriasis - reflex pupillary dilation as a muscle pulls the iris outward; occurs in response to a decrease in light or certain drugs |