I dunno. Did you look it up on wiki?
When I thing of the verb “wiki”, I think of putting something onto (into?) Wikipedia, not looking something up in it 
Fight my ignorance. I thought an intranet was the work network. So, do school me: what’s an intranet, an internet, and the Internet?
Heh. Where I work, it’s a WIKI, all caps, all the time. I’ve explained it to them, these are intelligent people, and they still do it. It’s not an acronym, assholes.
No, no, never, dead wrong in every case, absolutely not. Please don’t try to legitimize ignorance. This is like those grannies who interchange the terms “web” and “email” as in “I just logged onto email and checked the weather at weather.com”. The wiki genre of software is in wide use in companies everywhere now, this is not just a propellerhead distinction, it’s a matter of using correct unambiguous terminology.
Let’s go through this one time for everyone’s benefit:
The internet: A large-ish collection of computers linked together over a public network using internet protocol.
Intranet: Exactly like the internet, except only accessible through private networks, walled off from the outside.
Extranet: Parts of an organization’s intranet that can be accessed through the internet, for example so that employees can work from home.
The web: A collection of documents in different locations that contain links to one another. Access to these documents is provided by computers connected via the internet. In other words, the web is the smallest but best known function of the internet.
wiki: A web site running software that allows direct editing of the contents. Original name was “WikiWikiWeb” from the Hawaiian “WikiWiki” because it means “quick” and because it supplies the 2 W’s needed for the cute acronym. The original wiki, called “Portland Pattern Repository”, predated Wikipedia by a good 10 years or so. Wikis exist all over the internet as well as in intranets.
Wikipedia: A well-known online encyclopedia presented and edited as a wiki. Always “Wikipedia.” Never, never, never “on Wiki”, unless you want to sound like a complete tool. Nobody on Wikipedia makes this mistake, nobody who knows what they’re talking about makes this mistake.
A network is multiple computers connected together. An internetwork (later shortened to “internet”) is multiple networks connected together. Hence, if your company has completely separate networks in three cities, and puts in dedicated wiring and gateways to connect them, you now have an internet. Note that the word “an” goes with the lowercase “i” in internet.
When the whole friggin’ world connected up to Arpanet, it became known as “the Internet” (note the word “the” and the uppercase “I”). The old nonspecific word “internet” fell largely into disuse, but it still has its place. A totally secure set of networks connected together but disconnected from the Internet could still be considered an internet, though.
Once everybody had their networks hooked into the Internet, somebody decided we needed a new word for the parts of the network that were still private (not accessible from anywhere else on the Internet). That word is “intranet.” Basically, it’s your network, minus the public parts.
Brain Wreck also defined the word “extranet.” It’s a fuzzy term dreamed up by a marketing guy somewhere, and everybody seems to use it differently, rendering it pretty useless. I first came across it as a term for a database that customers could access to check order status and stock levels. In many cases, it’s just a password-protected Web site. In others, it’s a direct connection to non-Web data. In yet others, it’s all or part of an intranet. I refuse to use the word because it’s so fuzzy and nonspecific.
I use “wiki” as a verb in the following way:
Me: What did you think of my draft?
Him: “It was good except the first paragraph needs re-working, and I think the second part could be a bit clearer, and that thing about the elephants is just plain wrong, and there’s other stuff I can add to the bit about the wormhole.”
Me: Well, either you can dictate your changes to me over the phone, or I can send you the original and you can give it back when you’re done (meaning I can’t touch it until then), or else we can wiki it up and work on it together."