(also mail bomb) [Usenet]
1. v. To send, or urge others to send, massive amounts of email to a single system or person, esp. with intent to crash or spam the recipient's system. Sometimes done in retaliation for a perceived serious offense. Mailbombing is itself widely regarded as a serious offense — it can disrupt email traffic or other facilities for innocent users on the victim's system, and in extreme cases, even at upstream sites.
2. n. An automatic procedure with a similar effect.
3. n. The mail sent. Compare letterbomb, nastygram, BLOB (sense 2), list-bomb.