What does Q mean in speaker specifications?

Not googling it for ya, but it’s to do with damping. Basically,  the lower the Q #, the less energy stored at resonance. 

I wouldn’t worry too much about it. In general in this case, Q refers to the "bass alignment" and how the bass rolls off. A high q ( > 0.7) causes a bump at the bottom followed by a faster drop. A low Q ( < 0.7) causes the bass to roll off more slowly but without the hump.  A lot of smaller speakers use bump at the bottom to make them sound better. 

A Q of 0.7 is often referred to as optimally flat.  The bass alignment of a driver in a sealed enclosure is related to the size of the cabinet.  Smaller cabinet = higher Q.  Larger cabinet = lower Q. 

In a speaker like this though an optimally flat speaker may make it more easily to integrate with a sub at the -3 dB since it wont’ have a bump to minimize.

Truthfully, these are pretty technical terms which are great for designing a speaker but won’t matter much in room as the proximity to walls and floors will change the bass behavior a great deal.  In particular, don't try to get a perfect measuring speaker.  You want one that sounds great in the location you are planning for it.  While a Q of 0.7 may be maximally flat in an anechoic chamber it may also sound like it lacks bass in your room.

@erik_squires

Thanks for the detailed information! I asked because I have never seen the Q   listed in any other speakers specs!

PS - There are other Q’s in speaker design and measurements so don't get them confused but I'm pretty sure this is what is meant here.

In designing the alignment of the lowest frequency driver a great deal of artistic license must be allowed given the tradeoffs of speaker size, maximum bass output and expected placement.

A speaker designed for near-wall or desktop placement in general wants a lower Q.