go postal

Etymology
From +, from a number of incidents, mostly gun violence, perpetrated by disgruntled U.S. Postal Service workers on co-workers in the United States in the mid 1980s.

Verb

 * 1)  To become aggressive and erratic, especially due to stress; specifically, to carry out a shooting spree at a workplace environment; also  to become very angry; to lose one's temper.

Translations

 * French:
 * German:
 * Hungarian: ,
 * Portuguese: