1
general::
Phrase(s): drop a bomb(shell) [and] explode a bombshell; drop a brick
Fig. to announce shocking or startling news. • They really dropped a bombshell when they announced that the mayor would resign. • Friday is a good day to drop a bomb like that. It gives the business world the weekend to recover. • They must choose their words very carefully when they explode a bombshell like that. • They really dropped a brick when they told her the cause of her illness.
McGrawhill's American Idioms And Phrasal Verbs