I'm sorry, but what exactly is a "portal"?

So my boss sneaked up behind me today, as usual, while I was updating our "portal" web site, saw the huge "Welcome to our portal site" banner on the front page and said "Hey! Don't call it a portal; it's not!" Huh? Slightly stunned by the revelation, I switched over to Google and popped in the "define:portal" search expression, and low and behold, almost all of the Google definitions consistently define it as "a web site that is or is intended to be the first place people see when using the web. Typically, a portal site has a catalog of web sites, a search engine, or both. A portal site also may offer e-mail and other service to entice people to use that site as their main 'point of entry' (hence "portal" to the web)" [source].
WisdomPortal site also has a good list of definitions.

Well, slap me silly! I always thought it the other way around, that a portal would be an access point for the outside world, our customers, to reach into us, into our corporate information. What the heck?

Hypotheses
Either
1. I've dozed off in the past six years and am now technically clueless, or
2. the meaning of a "portal" has changed (read: evolved).

Proof
I took a chance that the former wasn't the case, and set out to prove the latter to myself. After some serious digging, I came upon this really good Portals 101 article that explained it all. The article quoted a more satisfactory definition to my taste: Portal is a term, generally synonymous with gateway, for a World Wide Web (WWW) site that is or proposes to be a major starting site for users when they get connected to the Web or that users tend to visit as an anchor site.
Ah hah! It is "synonymous with a gateway", not necessarily an Internet gateway, and as such, can function in both directions: inbound and outbound.

Apparently, there are different types/classes of portals:

1. Corporate or Enterprise (B2E) portals, (examples: corporate intranets)
   
2. eBusiness (B2B and B2C) portals (examples: mySAP, oraclesmallbusiness.com)
   
3. Personal (WAP) portals (examples: WebTV, OnStar), and
   
4. Public (Internet) portals (examples: Yahoo, Google, MSN)
   

So by the above definition, since the purpose of our company's portal site is to provide personalized service to our customers, it would fall under Type 2 (a B2C portal). So it IS a portal! It IS a portal! I'm not crazy after all. I'm not crazy after all!!! HAHAHA [klunk] [falling off soap box]

[climbing back on soap box]
Ergo, I've proven that both of my hypotheses are true! Hypothesis 2 is true because although the original general definitions are correct, there are specialized classifications of the general term, as seen above. And hypothesis 1 is also true; I must have dozed off a bit, because the "B2C Portal" concept has been in existence since at least 1999, if not earlier (read: "Critical Issues: The B2C Phenomenon", December 1999, PricewaterhouseCoopers LLP).

(Originally posted on: bloglines.com.)