e-blast
noun [ C ] internet & telecoms specialized uk/ˈiːˌblæst/ us/ˈiːˌblɑːst/
（为达到营销目的等）群发送电子邮件
an act of sending a copy of the same email to many people at the same time, for example by a company trying to sell something
Competition winners will be announced in our weekly e-blast. 竞赛获胜者将在我们每周的群发邮件中宣布。