What does the term "Speed" mean in a speaker?


I often hear people say "That speaker has great speed". What do they mean? I know the music isn't playing at a different pitch. Could it possibly be related to efficiency?
koestner
simmonmoon is correct. The correct term is transient response. Speakers with faster transient response tend to be more detailed and dynamic.
There are a bunch of rather silly terms out there in regard to audio equipment sound quality. Terms like pace and timing are frequently misapplied to speakers. The pace and timing of music is set by the musicians not the speakers. More poetic waxing.
Yep, transient response. I would say decay does not fall under the umbrella of speed or transient response but others may feel differently.

I just received the center channel that matches my Legacy Focus SE L/R Speakers. It mentions "speed" in their advertising also. Here’s part of their Ad


Legacy’s best center channel speaker has been updated to the Marquis XD. Featuring our 4" AMT ribbon, as found in the Legacy Dual Air Motion Tweeter system, and the 8" Italian crafted titanium encrusted midrange as utilized in the Aeris system, Marquis XD is on par with the speed of our best towers. These high precision drivers, a new crossover, and the incredible dual 12" ultra-linear bass drivers with 15 lb motors make it the best center speaker at any price. The dual 12" woofers of the Marquis XD deliver uprecedented linear output with snap and definition with rich upper bass and clean transition to the lower midrange.

Marquis XD can be placed above or below a 60” monitor, or behind a perforated projection screen in your home theater.

Thanks for all of this. Can amplifiers impact/covey speed differently? Seems they play a role as well...from peoples’ reviews. Is that right? 
Thanks!