|The Simple English Wiktionary has a definition for: bomb.|
A bomb is an explosive device that makes and lets out its energy very quickly and has a big shock wave. They have been used for centuries. Some bombs also throw out dangerous metal fragments, and some are firebombs.
A bomb is usually some kind of container filled with explosive material that is designed to destroy things when it is set off. The word bomb comes from the Greek word βόμβος (bombas), an onomatopoeic term with almost the same meaning as "boom" in English.