dilatate

Dilatate is a verb meaning to cause to dilate, or to expand and widen something. The form is found in older or technical texts and is closely related to dilate, dilation, and dilatation. In modern usage, dilate or dilation are more common, while dilatate appears primarily as a specialized or less frequent term.

In geometry, a dilatation (also called a dilation) is a transformation that enlarges or reduces figures with respect to a chosen center. Each point P maps to a point P' on the line from the center C through P, with CP' = k·CP, where k is the scale factor. If k > 1 the figure expands; 0 < k < 1 contract; a negative k also reverses orientation. Dilatations preserve straight lines and resemble the original shape, producing similarity.

In biology and medicine, dilatation or dilatation refers to the widening of a hollow organ or vessel. Examples include pupil dilatation (mydriasis), dilation of the bladder, intestines, or blood vessels. Dilatation can be physiological, pharmacological (drug-induced), or pathological (such as dilatation of heart chambers in certain cardiomyopathies).

The term also appears in other scientific contexts, including materials science and crystallography, where dilation can describe changes in lattice parameters under temperature or pressure. Etymology-wise, the word derives from Latin dilatare, meaning to widen.