1. A transformation which changes the size, and only the size, of a geometric figure.

2. An operation that provides a relatively flexible boundary to a fuzzy set; for a fuzzy set A with membership function m_A , a dilation of A is a fuzzy set whose membership function has the value [m_A(x )^β for every element x, where β is a fixed number that is greater than 0 and less than 1.

The act or process of stretching or expanding.