'Responsive,' in modern web design parlance, refers to the ability of your layout to respond to the different devices and screen sizes that may be accessing your site, and present your content in such a way that it doesn't force the user into non-native device modes of interaction (e.g., 1280 pixels wide means the user on the iPhone will be doing a lot of horizontal scrolling and zooming). So not a re-definition; just an additional meaning.

 
On 2012-07-08, at 1:58 PM, Dave Caroline wrote:

> I always understood responsive to be opposed to sluggish and a
> reference to speed.
> Do I see a redefinition starting up?
> 
> Dave Caroline