As a Noun: 1. The great effect of a situation or a person on a person. English = impact. 2. 3. The action of once object hitting another. English = impact. As a Verb or Adjective: 1. To have a great effect on a situation or person. English = impact on. 2. Having a major impact or effect, especially if it makes you realise a situation is more serious than you thought. English = impactful, sobering. 3.