Maybe this is more widely known and somehow I missed it for 15 years... but I've never seen it in an example or demonstrated to me.
Today I randomly happened to try "!" on a selector to negate it:
> vol move -vserver svmname -phase !completed
and it shows you moves in progress that are not completed.
So, what is this construct called? I ask because now I want to be able to look up what other things support it and if there are any other operators besides "!".