1. Any of the category of devices that is similar in design to an Ipod and plays MP3's. Any digital storage device capable of playing MP3s, that is not an Apple Ipod.
2. A small electronic device for playing MP3s over headphones. The original mass produced unit (Years before the Ipod) was the Diamond Rio complete with 32 Megabytes of flash memory and a slot for A SmartMedia Card that could at the time hold another 32 megabytes (They eventually maxed out at 128 megabytes.) This name came much later after the Ipod started dominating the market with its inferior technology, but superior marketing to yuppies, tweens and those that know very little about technology.
3. Any MP3 playing Pod.
I wanted to a new MP3 player, but those Nanos were overpriced and far inferior to what was actually available so I bought a Sandisk Mpod instead.