Internet rule declaring that if it exists you can jean it. Typically done by making it out of denim or adding something made of denim then changing the first sound to J- effectively making it a portmanteau of jean and the original word.

If the words starts with a consonant sound, it is swapped for a j. A j gets added to the front if it starts with vowel. Exceptions exist.
Two examples of rule 371 in action:

His jorts are hot.

My jarger keeps my wire from fraying.
by Well, TOO BAD!!!!! September 26, 2016
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