[im.pact] vb [L impactus, pp. of impingere to push against--more at impinge] vt (1601) 1 a: to fix firmly by or as if by packing or wedging b: to press together
2. a: to have an impact on: impinge on b: to strike forcefully; also: to cause to strike forcefully ~ vi 1: to have an impact
2: to impinge or make contact esp. forcefully -- im.pac.tive adj -- im.pac.tor also im.pact.er n
[2]im.pact n (1781) 1 a: an impinging or striking esp. of one body against another b: a forceful contact, collision, or onset; also: the impetus communicated in or as if in a collision
2: the force of impression of one thing on another: a significant or major effect "the ~ of science on our society" "an environmental ~ study"