Definition as per the Firefighter Terms website.
Jake - A term used to refer to a good firefighter. One story has the term originating from the corruption of the phrase “J-Key”. Years ago, the bed was the most expensive piece of furniture in a dwelling. Since firefighters were not as good at stopping fire as they are today, they would attempt to remove as many belongings as possible. The bed was too large to carry out in once piece and had to be disassembled using a bed key. The key was shaped like the letter J and was called a J-key
Well...there you go.
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