how do you gauge and judge "timing"?

I usually ask audiogon members which speaker has timing etc. I don't trust my own judgment, Neither did my X wife

Timing for me is about clean immediate attack alleviating smearing.  That has in recent years been my mainstay of component selection.  Immediate attack allows space between each vocal and instrument giving resolution/detail.  My 2 cents.

As I listen to the "musicianship" of each and every recording, timing imo, is when every musician is in sync with each other. My system is fantastic at this, and yes, I have heard many expensive systems in my lifetime that failed miserably at this, specifically in the bass region between drummers and bass players. Messy, sloppy, soggy, ill-defined...you get my point. It is a major "characteristic" of music listening that I enjoy, and I find extremely important. There is zero perfection with this hobby, and one needs to place these characteristics in an order that are most important to them. BTW, when listening to many of these systems, it did not matter (to me) if the sound staging was excellent, as this seems to be the trend for most listeners, which is fine. All about what you like.....I know what I like. I apologize for my "attitude" by those who take this the wrong way. My best, MrD.

If I have to listen to AC/DC to hear PRAT, please count me out… I far prefer Krall or Jones. 

In life timing is everything.  I guess it’s important when listening to music too.  I immediately thought of time alignment between speaker elements when I read the original post.  Appreciate the definitions posted.  Time has  come today - Time.  Now I’ve also got the Pink Floyd intro playing in my head which isn’t a bad thing.