[fr the Old West practice of having an armed guard with a shotgun riding beside the driver on the stagecoaches]
I am going to ride in the front passenger seat!: yelled Shotgun for the test drive
modifier(also blunderbuss) Very diffuse and general; indis-criminate; done in haste; scattergun: I hate it when the administrators make shotgun accusations/ But this is a blunderbuss technique (1930s+)
nounA matchmaker; a marriage broker
[1950s+; fr Yiddish shadchen, which is pronounced something like shotgun; perhaps reinforced by the notion of a shotgun wedding]