Having recently attended the New Adventures in Web Design Conference, some speakers touched on the subject of designing your content to fit a number of consumable mediums - that boiling down to view port size and mobile devices. This again was wrapped up in the term "Responsive Design". The term's origin was clarified both at the conference and from the A List Apart article:

"Recently, an emergent discipline called “responsive architecture” has begun asking how physical spaces can respond to the presence of people passing through them."

I don't feel the term "Responsive" is being used quite in the right context. For me, the above line does sum up how a website or application should behave if it is indeed "Responsive" - that is, to respond and alter it's behaviour based on the people that are interacting with it. To change it's overall design based on the constraints of the device it is being perceived  through is surely being "adaptive"?

To respond means to react to a certain action - you don't just "adapt" to a person poking you in the ribs, and you don't "respond" by merely bending your body around their poking finger (I certainly try not to anyway).

Likewise, a gas or liquid doesn't exactly "respond" to being put in a jar by taking up the free space, it "adapts" to the space it has been placed in.

Interestingly, at NACONF Dan Rubin's talk was based on thinking about the language we use when we're designing or developing - this is certainly one area I'm going to be keeping an eye on out of curiosity.

UPDATE:

Check out Harry Roberts' similar post for a far more eloquent summation on the responsive vs. adaptive story.