How do you say “collision” in German?

The various German words for “to collide” (or “to crash”) revolve around prallen (“to bump”) or stoßen (“to push”, “to prod”, “to jab”).

Kollidieren is also used, especially in reports of accidents or conflicting interests. Zusammenprallen and zusammenstoßen are useful everyday alternatives. Rather, Germans would say aufeinanderprallen, zusammenprallen, gegeneinanderprallen or zusammenstoßen to express multiple objects striking each other (usually accompanied by a loud noise).

Note that prallen can also mean “to blaze”, in the sense of “to shine intensely”. Its adjective is prall which can also mean “plump” or “bulging”.