The term describes a class of automobile with two seats, two doors, precise handling, brisk acceleration, and sharp braking — trading practical considerations such as passenger space, comfort, and cargo capacity — for driving enjoyment.
This definition recently came up in a conversation I had with my dad about the upcoming Jaguar XE. He read a post on roadandtrack.com that featured renderings of the vehicle, which said the timing of the concept will coincide with the anniversary of the vaunted E-type. He was confused because "The article makes it sound like Jag doesn’t already have the XK."
I too had read blurbs about this upcoming model claiming that it would be the spiritual successor to the E, and thought to myself, wasn't that the whole point of the XK? But herein lies the distinction between a sports car and a grand tourer. Back in the day, the E-type was one of the premier sports cars around, with great handling, decent power, and gorgeous lines. The original coupe was a two-seater, and the roadster was only offered that way.
Not until the stretched 2+2 version of the coupe arrived a few years after the E's debut did the model take on more characteristics of a grand tourer. The XK, on the other hand, was built as a GT from the start. Characterized by a comfortable ride, high speed stability and space for up to four people with luggage, grand tourers, as the name reflects, are meant to allow a long trip in total comfort.
Ferrari offers some great examples of this contrast. Its mid-engined base models, like the F430 and upcoming 458 Italia, are designed to get around a track the fastest way possible. They trade comfort for speed, and the ultimate Ferrari sports cars, like the 430 Scuderia, strip out all comfort items, like radio, A/C and sound deadening.
The 612 Scaglietti, on the other hand, is the Ferrari built for four. You can run it for hours at superlegal speeds and, due to what Ferrari calls its "unprecedented comfort", get out at the other end feeling fresh as a daisy. Ferrari even classifies it as a "berlinetta", which translates to "little saloon", a saloon being the European term for a sedan.
In the context of Jag's lineup, the fact that the XE will be a two-seat sports car means that it will compete more with the Porsche Boxster/Cayman than the Mercedes-Benz SL or BMW 6-Series, as the XK does. Will Jaguar customers go for a true sports car? I think that's a big wild card. But at least we know that, even while the XK remains, the new car has a raison d'être.