So how did those Big Gulp-sized beer transportation vessels get their name? Nobody knows! Beer investigators have been chasing their tails for years, and, although there's no conclusive evidence, there are a few popular theories worth learning for National Growler Day.
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The common belief is that the earliest versions of growlers were steel pails. The sudsmen at Growler Station and BeerAdvocate, plus pretty much every bar-stool history essay, assert that, as these beer vessels were in transport, the metal lids would rattle around and cause the carbonation to escape from the bucket, thus making a rumbling sound.
The beer container merchants at Bottless.net assert that although beer was once sold in pints, bartenders would fill a growler with nearly a quart of suds (aka two pints) because there weren't measurement standards in place yet. Often, bartenders and beer drinkers would argue about how much booze should be poured into the pail, and customers would sometimes whine about it like little dogs.
World Wide Words gets all etymological on that bitch (dog reference!) by digging up (another one!) a Harper's issue from 1893 in which they mention the practice of "rushing the growler", which referred to children delivering beer to their parents. That was derived from the phrase "chasing the duck", hunting slang for when a dog would fetch fallen prey, which you probably know about mainly from Duck Hunt.
Lastly, BeerNexus notes that beer deliveries often arrived during lunch breaks before the workers had eaten, so their stomachs were making the same types of sounds that today's parenting groups would make if they found out that kids were acting as walking bartenders.
Dan Gentileis a staff writer on Thrillist's national food and drink team. He owns both of the growlers pictured above, one is named Peanut and the other is named Brewslayer. Follow him to really interesting stories about his dog at@Dannosphere.