- invasion index
An index devised by Abercrombie & Heaysman as a means to estimate the invasiveness of cells in vitro. The index is derived from measurements on confronted explants of the cells and embryonic chick heart fibroblasts growing in tissue culture: it is the ratio of the estimated movement, had the cells not been hindered, and the actual movement in the zone in which collision occurs.
Dictionary of molecular biology. 2004.