The very tiny pockets found in jeans, usually located inside the front pockets, are commonly referred to as watch pockets or coin pockets. These small pockets have a historical purpose but are now mainly used for carrying small items like coins, keys, or jewelry.

The original purpose of the watch pocket dates back to the 19th century when pocket watches were more common. People would use these small pockets to safely store their pocket watches, keeping them secure and preventing them from getting scratched or damaged. The design of jeans has evolved over time, and while pocket watches are not as prevalent today, the small pocket remains as a vestige of its original function.