dilation

nouns

a lengthy discussion (spoken or written) on a particular topic
dilation
is derived from
dilate
is a type of (narrower)
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"
discourse, discussion, treatment
the act of expanding an aperture
"the dilation of the pupil of the eye"
dilatation, dilation
is derived from
dilate