Origin of the Word
According to the Yahoo! Groups forum Global Positioning Stash Hunt (gpsstash), the first recorded geocache placement was by Dave Ulmer on May 3, 2000 and called a GPS Stash Hunt. Since that time the activity has been referred to as GPS-stashing, GPS stash hunting, and even geostashing. The original Yahoo! Group is still active, by the way, even though it doesn’t seem to get nearly as much traffic as it did in its initial year of founding.
So, why was the term “stash" quickly dropped and substituted with the word “cache"? During the early days of the Global Position Stash Hunt group, there was some discussion concerning an appropriate name for the activity. Several ideas for a permanent name were bandied about – including planeteering and GPS trove hunting as well as almost every variation of phrases containing the words GPS and stash that you can think of.
Then, in one note on the discussion forum, Matt Stum pointed out that the term “stash" might cause some people to associate the word with illegal activities (such as a drug stash). As an alternative, he suggested replacing “stash" with “cache" since the latter term had more positive connotations. Stum also noted that, in addition to its other meanings, the term “cache" had once been used to describe areas where explorers left provisions in places where they could be retrieved at a later date, sometimes even shared among groups of people.
It didn't take time for the word "geocaching" to catch on, even though some veterans will still occasionally refer to the hobby as geostashing or one of its other names. The game has come a long way over its short life span and it still continues to evolve, but it looks like the name "geocaching" is going to stick.