bombo

Worth knowing that the word began as a noise. Greek bombos was a deep humming or booming, Latin took it as bombus, and only much later did it attach to the object that made the boom. That history is still audible in bombasta, bombastic, which is about loud empty sound rather than explosives.

The figurative use is as live in Esperanto as in English, and it is the sense a learner is far more likely to need: la novaĵo falis kiel bombo is exactly the English the news landed like a bombshell, an announcement that stops a room. Bomba in casual modern usage can mean sensational in the same slightly breathless way.

The derivations behave predictably: bombi is to bomb, bombado is the bombing, and bombisto is the one who does it. The neutral technical family sits alongside - eksplodi (to explode), eksplodaĵo (an explosive), danĝero - and in a museum caption you would more often meet senaktivigita bombo, a bomb that has been made safe.