I was googling the reason for why it's called "shotgun" to ride beside the driver when it suddenly hit me - why on Earth is the firearm called "shotgun"?! Is there any other kind of a gun than one ...
Is it the word "between", but truncated, or a portmanteau of "in between" and "teen"?
The Online Etymology Dictionary unsurprisingly says brainstorm is from the combination of brain and storm. What I want to know is whether or not this neologism was an intentional pun on the word ...