IPA: /kəˈlɪʒənəli/
KK: /kəˈlɪʒənəli/
In a manner that relates to collisions or impacts between objects.
The two cars collided collisionally, causing significant damage.
Collisionally → It is formed from "collide" (from Latin "collidere", meaning to strike together) and the suffix "-ally" (meaning in a manner). The word "collisionally" refers to something that occurs in a manner related to a collision.
Think of things 'striking together' ('collide') and how they happen 'in a manner' ('-ally') — that's what collisionally means.