Someone who hogs, or "whores" all of the valuable weapons in the video game Halo. The term "weapon whore" can be made more specific by replacing the term "weapon" with the valuable object.

When you eat dirt for the first time and leave your family to build a shack in the woods

In any given multiplayer First Person Shooter (Especially ones with customiseable content eg CoD 4), a weapon whore is a person who goes around picking up and using people's guns. This is generally due to either: 1. Primary weapon has run out 2. Bad sidearm 3. Beginner and therefore crappy weapons.

Although generally not a bad thing, it can be used as an insult