Winnure is game talk. Online games such as mmorpgs on the internet or xboxlive games ect. It falls into the same category as: Winner;Win. It can be used as an insult, or a compliment. It's pronounced how you see it: WIN - YER.
It can be used, for an example: You're on Runescape, and you're a level 57 in a clan along with other levels higher than you, and the highest level on the opposing clan comes and fights you first, making him look like a complete utter, homosexual.
Level124: dude, i'm totally going to pwn you
Level24: fool, i'm like 100 levels under you
Level: Wow, dude you're such a winnure.